Merge pull request #3722 from fjl/hexutil-text-unmarshal

common/hexutil: implement TextMarshaler, TextUnmarshaler

9 files changed, 275 insertions, 114 deletions

diff --git a/common/hexutil/hexutil.go b/common/hexutil/hexutil.go
index 4ec0ee8e6..6b128ae36 100644
--- a/common/hexutil/hexutil.go
+++ b/common/hexutil/hexutil.go
@@ -49,6 +49,7 @@ var (
 	ErrOddLength     = errors.New("hex string has odd length")
 	ErrUint64Range   = errors.New("hex number does not fit into 64 bits")
 	ErrUintRange     = fmt.Errorf("hex number does not fit into %d bits", uintBits)
+	ErrBig256Range   = errors.New("hex number does not fit into 256 bits")
 )
 
 // Decode decodes a hex string with 0x prefix.
@@ -59,7 +60,11 @@ func Decode(input string) ([]byte, error) {
 	if !has0xPrefix(input) {
 		return nil, ErrMissingPrefix
 	}
-	return hex.DecodeString(input[2:])
+	b, err := hex.DecodeString(input[2:])
+	if err != nil {
+		err = mapError(err)
+	}
+	return b, err
 }
 
 // MustDecode decodes a hex string with 0x prefix. It panics for invalid input.
@@ -126,11 +131,15 @@ func init() {
 }
 
 // DecodeBig decodes a hex string with 0x prefix as a quantity.
+// Numbers larger than 256 bits are not accepted.
 func DecodeBig(input string) (*big.Int, error) {
 	raw, err := checkNumber(input)
 	if err != nil {
 		return nil, err
 	}
+	if len(raw) > 64 {
+		return nil, ErrBig256Range
+	}
 	words := make([]big.Word, len(raw)/bigWordNibbles+1)
 	end := len(raw)
 	for i := range words {
@@ -169,7 +178,7 @@ func EncodeBig(bigint *big.Int) string {
 	if nbits == 0 {
 		return "0x0"
 	}
-	return fmt.Sprintf("0x%x", bigint)
+	return fmt.Sprintf("%#x", bigint)
 }
 
 func has0xPrefix(input string) bool {
diff --git a/common/hexutil/hexutil_test.go b/common/hexutil/hexutil_test.go
index 324e9d348..ed6fccc3c 100644
--- a/common/hexutil/hexutil_test.go
+++ b/common/hexutil/hexutil_test.go
@@ -18,7 +18,6 @@ package hexutil
 
 import (
 	"bytes"
-	"encoding/hex"
 	"math/big"
 	"testing"
 )
@@ -29,9 +28,10 @@ type marshalTest struct {
 }
 
 type unmarshalTest struct {
-	input   string
-	want    interface{}
-	wantErr error
+	input        string
+	want         interface{}
+	wantErr      error // if set, decoding must fail on any platform
+	wantErr32bit error // if set, decoding must fail on 32bit platforms (used for Uint tests)
 }
 
 var (
@@ -47,6 +47,7 @@ var (
 		{referenceBig("ff"), "0xff"},
 		{referenceBig("112233445566778899aabbccddeeff"), "0x112233445566778899aabbccddeeff"},
 		{referenceBig("80a7f2c1bcc396c00"), "0x80a7f2c1bcc396c00"},
+		{referenceBig("-80a7f2c1bcc396c00"), "-0x80a7f2c1bcc396c00"},
 	}
 
 	encodeUint64Tests = []marshalTest{
@@ -56,14 +57,21 @@ var (
 		{uint64(0x1122334455667788), "0x1122334455667788"},
 	}
 
+	encodeUintTests = []marshalTest{
+		{uint(0), "0x0"},
+		{uint(1), "0x1"},
+		{uint(0xff), "0xff"},
+		{uint(0x11223344), "0x11223344"},
+	}
+
 	decodeBytesTests = []unmarshalTest{
 		// invalid
 		{input: ``, wantErr: ErrEmptyString},
 		{input: `0`, wantErr: ErrMissingPrefix},
-		{input: `0x0`, wantErr: hex.ErrLength},
-		{input: `0x023`, wantErr: hex.ErrLength},
-		{input: `0xxx`, wantErr: hex.InvalidByteError('x')},
-		{input: `0x01zz01`, wantErr: hex.InvalidByteError('z')},
+		{input: `0x0`, wantErr: ErrOddLength},
+		{input: `0x023`, wantErr: ErrOddLength},
+		{input: `0xxx`, wantErr: ErrSyntax},
+		{input: `0x01zz01`, wantErr: ErrSyntax},
 		// valid
 		{input: `0x`, want: []byte{}},
 		{input: `0X`, want: []byte{}},
@@ -83,6 +91,10 @@ var (
 		{input: `0x01`, wantErr: ErrLeadingZero},
 		{input: `0xx`, wantErr: ErrSyntax},
 		{input: `0x1zz01`, wantErr: ErrSyntax},
+		{
+			input:   `0x10000000000000000000000000000000000000000000000000000000000000000`,
+			wantErr: ErrBig256Range,
+		},
 		// valid
 		{input: `0x0`, want: big.NewInt(0)},
 		{input: `0x2`, want: big.NewInt(0x2)},
@@ -99,6 +111,10 @@ var (
 			input: `0xffffffffffffffffffffffffffffffffffff`,
 			want:  referenceBig("ffffffffffffffffffffffffffffffffffff"),
 		},
+		{
+			input: `0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff`,
+			want:  referenceBig("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"),
+		},
 	}
 
 	decodeUint64Tests = []unmarshalTest{
diff --git a/common/hexutil/json.go b/common/hexutil/json.go
index 7e4736dd6..23393ed2c 100644
--- a/common/hexutil/json.go
+++ b/common/hexutil/json.go
@@ -25,28 +25,33 @@ import (
 )
 
 var (
-	jsonNull          = []byte("null")
-	jsonZero          = []byte(`"0x0"`)
-	errNonString      = errors.New("cannot unmarshal non-string as hex data")
-	errNegativeBigInt = errors.New("hexutil.Big: can't marshal negative integer")
+	textZero     = []byte(`0x0`)
+	errNonString = errors.New("cannot unmarshal non-string as hex data")
 )
 
 // Bytes marshals/unmarshals as a JSON string with 0x prefix.
 // The empty slice marshals as "0x".
 type Bytes []byte
 
-// MarshalJSON implements json.Marshaler.
-func (b Bytes) MarshalJSON() ([]byte, error) {
-	result := make([]byte, len(b)*2+4)
-	copy(result, `"0x`)
-	hex.Encode(result[3:], b)
-	result[len(result)-1] = '"'
+// MarshalText implements encoding.TextMarshaler
+func (b Bytes) MarshalText() ([]byte, error) {
+	result := make([]byte, len(b)*2+2)
+	copy(result, `0x`)
+	hex.Encode(result[2:], b)
 	return result, nil
 }
 
 // UnmarshalJSON implements json.Unmarshaler.
 func (b *Bytes) UnmarshalJSON(input []byte) error {
-	raw, err := checkJSON(input)
+	if !isString(input) {
+		return errNonString
+	}
+	return b.UnmarshalText(input[1 : len(input)-1])
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler.
+func (b *Bytes) UnmarshalText(input []byte) error {
+	raw, err := checkText(input)
 	if err != nil {
 		return err
 	}
@@ -64,17 +69,11 @@ func (b Bytes) String() string {
 	return Encode(b)
 }
 
-// UnmarshalJSON decodes input as a JSON string with 0x prefix. The length of out
+// UnmarshalFixedText decodes the input as a string with 0x prefix. The length of out
 // determines the required input length. This function is commonly used to implement the
-// UnmarshalJSON method for fixed-size types:
-//
-//     type Foo [8]byte
-//
-//     func (f *Foo) UnmarshalJSON(input []byte) error {
-//         return hexutil.UnmarshalJSON("Foo", input, f[:])
-//     }
-func UnmarshalJSON(typname string, input, out []byte) error {
-	raw, err := checkJSON(input)
+// UnmarshalText method for fixed-size types.
+func UnmarshalFixedText(typname string, input, out []byte) error {
+	raw, err := checkText(input)
 	if err != nil {
 		return err
 	}
@@ -91,34 +90,36 @@ func UnmarshalJSON(typname string, input, out []byte) error {
 	return nil
 }
 
-// Big marshals/unmarshals as a JSON string with 0x prefix. The zero value marshals as
-// "0x0". Negative integers are not supported at this time. Attempting to marshal them
-// will return an error.
+// Big marshals/unmarshals as a JSON string with 0x prefix.
+// The zero value marshals as "0x0".
+//
+// Negative integers are not supported at this time. Attempting to marshal them will
+// return an error. Values larger than 256bits are rejected by Unmarshal but will be
+// marshaled without error.
 type Big big.Int
 
-// MarshalJSON implements json.Marshaler.
-func (b *Big) MarshalJSON() ([]byte, error) {
-	if b == nil {
-		return jsonNull, nil
-	}
-	bigint := (*big.Int)(b)
-	if bigint.Sign() == -1 {
-		return nil, errNegativeBigInt
-	}
-	nbits := bigint.BitLen()
-	if nbits == 0 {
-		return jsonZero, nil
-	}
-	enc := fmt.Sprintf(`"0x%x"`, bigint)
-	return []byte(enc), nil
+// MarshalText implements encoding.TextMarshaler
+func (b Big) MarshalText() ([]byte, error) {
+	return []byte(EncodeBig((*big.Int)(&b))), nil
 }
 
 // UnmarshalJSON implements json.Unmarshaler.
 func (b *Big) UnmarshalJSON(input []byte) error {
-	raw, err := checkNumberJSON(input)
+	if !isString(input) {
+		return errNonString
+	}
+	return b.UnmarshalText(input[1 : len(input)-1])
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler
+func (b *Big) UnmarshalText(input []byte) error {
+	raw, err := checkNumberText(input)
 	if err != nil {
 		return err
 	}
+	if len(raw) > 64 {
+		return ErrBig256Range
+	}
 	words := make([]big.Word, len(raw)/bigWordNibbles+1)
 	end := len(raw)
 	for i := range words {
@@ -156,18 +157,25 @@ func (b *Big) String() string {
 // The zero value marshals as "0x0".
 type Uint64 uint64
 
-// MarshalJSON implements json.Marshaler.
-func (b Uint64) MarshalJSON() ([]byte, error) {
-	buf := make([]byte, 3, 12)
-	copy(buf, `"0x`)
+// MarshalText implements encoding.TextMarshaler.
+func (b Uint64) MarshalText() ([]byte, error) {
+	buf := make([]byte, 2, 10)
+	copy(buf, `0x`)
 	buf = strconv.AppendUint(buf, uint64(b), 16)
-	buf = append(buf, '"')
 	return buf, nil
 }
 
 // UnmarshalJSON implements json.Unmarshaler.
 func (b *Uint64) UnmarshalJSON(input []byte) error {
-	raw, err := checkNumberJSON(input)
+	if !isString(input) {
+		return errNonString
+	}
+	return b.UnmarshalText(input[1 : len(input)-1])
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler
+func (b *Uint64) UnmarshalText(input []byte) error {
+	raw, err := checkNumberText(input)
 	if err != nil {
 		return err
 	}
@@ -196,19 +204,27 @@ func (b Uint64) String() string {
 // The zero value marshals as "0x0".
 type Uint uint
 
-// MarshalJSON implements json.Marshaler.
-func (b Uint) MarshalJSON() ([]byte, error) {
-	return Uint64(b).MarshalJSON()
+// MarshalText implements encoding.TextMarshaler.
+func (b Uint) MarshalText() ([]byte, error) {
+	return Uint64(b).MarshalText()
 }
 
 // UnmarshalJSON implements json.Unmarshaler.
 func (b *Uint) UnmarshalJSON(input []byte) error {
+	if !isString(input) {
+		return errNonString
+	}
+	return b.UnmarshalText(input[1 : len(input)-1])
+}
+
+// UnmarshalText implements encoding.TextUnmarshaler.
+func (b *Uint) UnmarshalText(input []byte) error {
 	var u64 Uint64
-	err := u64.UnmarshalJSON(input)
-	if err != nil {
-		return err
-	} else if u64 > Uint64(^uint(0)) {
+	err := u64.UnmarshalText(input)
+	if u64 > Uint64(^uint(0)) || err == ErrUint64Range {
 		return ErrUintRange
+	} else if err != nil {
+		return err
 	}
 	*b = Uint(u64)
 	return nil
@@ -227,28 +243,21 @@ func bytesHave0xPrefix(input []byte) bool {
 	return len(input) >= 2 && input[0] == '0' && (input[1] == 'x' || input[1] == 'X')
 }
 
-func checkJSON(input []byte) (raw []byte, err error) {
-	if !isString(input) {
-		return nil, errNonString
-	}
-	if len(input) == 2 {
+func checkText(input []byte) ([]byte, error) {
+	if len(input) == 0 {
 		return nil, nil // empty strings are allowed
 	}
-	if !bytesHave0xPrefix(input[1:]) {
+	if !bytesHave0xPrefix(input) {
 		return nil, ErrMissingPrefix
 	}
-	input = input[3 : len(input)-1]
+	input = input[2:]
 	if len(input)%2 != 0 {
 		return nil, ErrOddLength
 	}
 	return input, nil
 }
 
-func checkNumberJSON(input []byte) (raw []byte, err error) {
-	if !isString(input) {
-		return nil, errNonString
-	}
-	input = input[1 : len(input)-1]
+func checkNumberText(input []byte) (raw []byte, err error) {
 	if len(input) == 0 {
 		return nil, nil // empty strings are allowed
 	}
diff --git a/common/hexutil/json_example_test.go b/common/hexutil/json_example_test.go
new file mode 100644
index 000000000..80180d918
--- /dev/null
+++ b/common/hexutil/json_example_test.go
@@ -0,0 +1,45 @@
+// Copyright 2017 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 <http://www.gnu.org/licenses/>.
+
+package hexutil_test
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/ethereum/go-ethereum/common/hexutil"
+)
+
+type MyType [5]byte
+
+func (v *MyType) UnmarshalText(input []byte) error {
+	return hexutil.UnmarshalFixedText("MyType", input, v[:])
+}
+
+func (v MyType) String() string {
+	return hexutil.Bytes(v[:]).String()
+}
+
+func ExampleUnmarshalFixedText() {
+	var v1, v2 MyType
+	fmt.Println("v1 error:", json.Unmarshal([]byte(`"0x01"`), &v1))
+	fmt.Println("v2 error:", json.Unmarshal([]byte(`"0x0101010101"`), &v2))
+	fmt.Println("v2:", v2)
+	// Output:
+	// v1 error: hex string has length 2, want 10 for MyType
+	// v2 error: <nil>
+	// v2: 0x0101010101
+}
diff --git a/common/hexutil/json_test.go b/common/hexutil/json_test.go
index 290bf9ca2..af7f44915 100644
--- a/common/hexutil/json_test.go
+++ b/common/hexutil/json_test.go
@@ -19,6 +19,8 @@ package hexutil
 import (
 	"bytes"
 	"encoding/hex"
+	"encoding/json"
+	"errors"
 	"math/big"
 	"testing"
 )
@@ -55,9 +57,11 @@ func referenceBytes(s string) []byte {
 	return b
 }
 
+var errJSONEOF = errors.New("unexpected end of JSON input")
+
 var unmarshalBytesTests = []unmarshalTest{
 	// invalid encoding
-	{input: "", wantErr: errNonString},
+	{input: "", wantErr: errJSONEOF},
 	{input: "null", wantErr: errNonString},
 	{input: "10", wantErr: errNonString},
 	{input: `"0"`, wantErr: ErrMissingPrefix},
@@ -80,7 +84,7 @@ var unmarshalBytesTests = []unmarshalTest{
 func TestUnmarshalBytes(t *testing.T) {
 	for _, test := range unmarshalBytesTests {
 		var v Bytes
-		err := v.UnmarshalJSON([]byte(test.input))
+		err := json.Unmarshal([]byte(test.input), &v)
 		if !checkError(t, test.input, err, test.wantErr) {
 			continue
 		}
@@ -104,7 +108,7 @@ func BenchmarkUnmarshalBytes(b *testing.B) {
 func TestMarshalBytes(t *testing.T) {
 	for _, test := range encodeBytesTests {
 		in := test.input.([]byte)
-		out, err := Bytes(in).MarshalJSON()
+		out, err := json.Marshal(Bytes(in))
 		if err != nil {
 			t.Errorf("%x: %v", in, err)
 			continue
@@ -122,7 +126,7 @@ func TestMarshalBytes(t *testing.T) {
 
 var unmarshalBigTests = []unmarshalTest{
 	// invalid encoding
-	{input: "", wantErr: errNonString},
+	{input: "", wantErr: errJSONEOF},
 	{input: "null", wantErr: errNonString},
 	{input: "10", wantErr: errNonString},
 	{input: `"0"`, wantErr: ErrMissingPrefix},
@@ -130,6 +134,10 @@ var unmarshalBigTests = []unmarshalTest{
 	{input: `"0x01"`, wantErr: ErrLeadingZero},
 	{input: `"0xx"`, wantErr: ErrSyntax},
 	{input: `"0x1zz01"`, wantErr: ErrSyntax},
+	{
+		input:   `"0x10000000000000000000000000000000000000000000000000000000000000000"`,
+		wantErr: ErrBig256Range,
+	},
 
 	// valid encoding
 	{input: `""`, want: big.NewInt(0)},
@@ -148,12 +156,16 @@ var unmarshalBigTests = []unmarshalTest{
 		input: `"0xffffffffffffffffffffffffffffffffffff"`,
 		want:  referenceBig("ffffffffffffffffffffffffffffffffffff"),
 	},
+	{
+		input: `"0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"`,
+		want:  referenceBig("ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff"),
+	},
 }
 
 func TestUnmarshalBig(t *testing.T) {
 	for _, test := range unmarshalBigTests {
 		var v Big
-		err := v.UnmarshalJSON([]byte(test.input))
+		err := json.Unmarshal([]byte(test.input), &v)
 		if !checkError(t, test.input, err, test.wantErr) {
 			continue
 		}
@@ -177,7 +189,7 @@ func BenchmarkUnmarshalBig(b *testing.B) {
 func TestMarshalBig(t *testing.T) {
 	for _, test := range encodeBigTests {
 		in := test.input.(*big.Int)
-		out, err := (*Big)(in).MarshalJSON()
+		out, err := json.Marshal((*Big)(in))
 		if err != nil {
 			t.Errorf("%d: %v", in, err)
 			continue
@@ -195,7 +207,7 @@ func TestMarshalBig(t *testing.T) {
 
 var unmarshalUint64Tests = []unmarshalTest{
 	// invalid encoding
-	{input: "", wantErr: errNonString},
+	{input: "", wantErr: errJSONEOF},
 	{input: "null", wantErr: errNonString},
 	{input: "10", wantErr: errNonString},
 	{input: `"0"`, wantErr: ErrMissingPrefix},
@@ -219,7 +231,7 @@ var unmarshalUint64Tests = []unmarshalTest{
 func TestUnmarshalUint64(t *testing.T) {
 	for _, test := range unmarshalUint64Tests {
 		var v Uint64
-		err := v.UnmarshalJSON([]byte(test.input))
+		err := json.Unmarshal([]byte(test.input), &v)
 		if !checkError(t, test.input, err, test.wantErr) {
 			continue
 		}
@@ -241,7 +253,7 @@ func BenchmarkUnmarshalUint64(b *testing.B) {
 func TestMarshalUint64(t *testing.T) {
 	for _, test := range encodeUint64Tests {
 		in := test.input.(uint64)
-		out, err := Uint64(in).MarshalJSON()
+		out, err := json.Marshal(Uint64(in))
 		if err != nil {
 			t.Errorf("%d: %v", in, err)
 			continue
@@ -256,3 +268,72 @@ func TestMarshalUint64(t *testing.T) {
 		}
 	}
 }
+
+func TestMarshalUint(t *testing.T) {
+	for _, test := range encodeUintTests {
+		in := test.input.(uint)
+		out, err := json.Marshal(Uint(in))
+		if err != nil {
+			t.Errorf("%d: %v", in, err)
+			continue
+		}
+		if want := `"` + test.want + `"`; string(out) != want {
+			t.Errorf("%d: MarshalJSON output mismatch: got %q, want %q", in, out, want)
+			continue
+		}
+		if out := (Uint)(in).String(); out != test.want {
+			t.Errorf("%x: String mismatch: got %q, want %q", in, out, test.want)
+			continue
+		}
+	}
+}
+
+var (
+	// These are variables (not constants) to avoid constant overflow
+	// checks in the compiler on 32bit platforms.
+	maxUint33bits = uint64(^uint32(0)) + 1
+	maxUint64bits = ^uint64(0)
+)
+
+var unmarshalUintTests = []unmarshalTest{
+	// invalid encoding
+	{input: "", wantErr: errJSONEOF},
+	{input: "null", wantErr: errNonString},
+	{input: "10", wantErr: errNonString},
+	{input: `"0"`, wantErr: ErrMissingPrefix},
+	{input: `"0x"`, wantErr: ErrEmptyNumber},
+	{input: `"0x01"`, wantErr: ErrLeadingZero},
+	{input: `"0x100000000"`, want: uint(maxUint33bits), wantErr32bit: ErrUintRange},
+	{input: `"0xfffffffffffffffff"`, wantErr: ErrUintRange},
+	{input: `"0xx"`, wantErr: ErrSyntax},
+	{input: `"0x1zz01"`, wantErr: ErrSyntax},
+
+	// valid encoding
+	{input: `""`, want: uint(0)},
+	{input: `"0x0"`, want: uint(0)},
+	{input: `"0x2"`, want: uint(0x2)},
+	{input: `"0x2F2"`, want: uint(0x2f2)},
+	{input: `"0X2F2"`, want: uint(0x2f2)},
+	{input: `"0x1122aaff"`, want: uint(0x1122aaff)},
+	{input: `"0xbbb"`, want: uint(0xbbb)},
+	{input: `"0xffffffff"`, want: uint(0xffffffff)},
+	{input: `"0xffffffffffffffff"`, want: uint(maxUint64bits), wantErr32bit: ErrUintRange},
+}
+
+func TestUnmarshalUint(t *testing.T) {
+	for _, test := range unmarshalUintTests {
+		var v Uint
+		err := json.Unmarshal([]byte(test.input), &v)
+		if uintBits == 32 && test.wantErr32bit != nil {
+			checkError(t, test.input, err, test.wantErr32bit)
+			continue
+		}
+		if !checkError(t, test.input, err, test.wantErr) {
+			continue
+		}
+		if uint(v) != test.want.(uint) {
+			t.Errorf("input %s: value mismatch: got %d, want %d", test.input, v, test.want)
+			continue
+		}
+	}
+}
diff --git a/common/types.go b/common/types.go
index 0c9e68903..9c50beb13 100644
--- a/common/types.go
+++ b/common/types.go
@@ -71,14 +71,14 @@ func (h Hash) Format(s fmt.State, c rune) {
 	fmt.Fprintf(s, "%"+string(c), h[:])
 }
 
-// UnmarshalJSON parses a hash in its hex from to a hash.
-func (h *Hash) UnmarshalJSON(input []byte) error {
-	return hexutil.UnmarshalJSON("Hash", input, h[:])
+// UnmarshalText parses a hash in hex syntax.
+func (h *Hash) UnmarshalText(input []byte) error {
+	return hexutil.UnmarshalFixedText("Hash", input, h[:])
 }
 
-// Serialize given hash to JSON
-func (h Hash) MarshalJSON() ([]byte, error) {
-	return hexutil.Bytes(h[:]).MarshalJSON()
+// MarshalText returns the hex representation of h.
+func (h Hash) MarshalText() ([]byte, error) {
+	return hexutil.Bytes(h[:]).MarshalText()
 }
 
 // Sets the hash to the value of b. If b is larger than len(h) it will panic
@@ -171,14 +171,14 @@ func (a *Address) Set(other Address) {
 	}
 }
 
-// Serialize given address to JSON
-func (a Address) MarshalJSON() ([]byte, error) {
-	return hexutil.Bytes(a[:]).MarshalJSON()
+// MarshalText returns the hex representation of a.
+func (a Address) MarshalText() ([]byte, error) {
+	return hexutil.Bytes(a[:]).MarshalText()
 }
 
-// Parse address from raw json data
-func (a *Address) UnmarshalJSON(input []byte) error {
-	return hexutil.UnmarshalJSON("Address", input, a[:])
+// UnmarshalText parses a hash in hex syntax.
+func (a *Address) UnmarshalText(input []byte) error {
+	return hexutil.UnmarshalFixedText("Address", input, a[:])
 }
 
 // PP Pretty Prints a byte slice in the following format:
diff --git a/common/types_test.go b/common/types_test.go
index e84780f43..9f9d8b767 100644
--- a/common/types_test.go
+++ b/common/types_test.go
@@ -17,6 +17,7 @@
 package common
 
 import (
+	"encoding/json"
 	"math/big"
 	"strings"
 	"testing"
@@ -37,7 +38,6 @@ func TestBytesConversion(t *testing.T) {
 }
 
 func TestHashJsonValidation(t *testing.T) {
-	var h Hash
 	var tests = []struct {
 		Prefix string
 		Size   int
@@ -52,7 +52,8 @@ func TestHashJsonValidation(t *testing.T) {
 	}
 	for _, test := range tests {
 		input := `"` + test.Prefix + strings.Repeat("0", test.Size) + `"`
-		err := h.UnmarshalJSON([]byte(input))
+		var v Hash
+		err := json.Unmarshal([]byte(input), &v)
 		if err == nil {
 			if test.Error != "" {
 				t.Errorf("%s: error mismatch: have nil, want %q", input, test.Error)
@@ -66,7 +67,6 @@ func TestHashJsonValidation(t *testing.T) {
 }
 
 func TestAddressUnmarshalJSON(t *testing.T) {
-	var a Address
 	var tests = []struct {
 		Input     string
 		ShouldErr bool
@@ -81,7 +81,8 @@ func TestAddressUnmarshalJSON(t *testing.T) {
 		{`"0x0000000000000000000000000000000000000010"`, false, big.NewInt(16)},
 	}
 	for i, test := range tests {
-		err := a.UnmarshalJSON([]byte(test.Input))
+		var v Address
+		err := json.Unmarshal([]byte(test.Input), &v)
 		if err != nil && !test.ShouldErr {
 			t.Errorf("test #%d: unexpected error: %v", i, err)
 		}
@@ -89,8 +90,8 @@ func TestAddressUnmarshalJSON(t *testing.T) {
 			if test.ShouldErr {
 				t.Errorf("test #%d: expected error, got none", i)
 			}
-			if a.Big().Cmp(test.Output) != 0 {
-				t.Errorf("test #%d: address mismatch: have %v, want %v", i, a.Big(), test.Output)
+			if v.Big().Cmp(test.Output) != 0 {
+				t.Errorf("test #%d: address mismatch: have %v, want %v", i, v.Big(), test.Output)
 			}
 		}
 	}
diff --git a/core/types/block.go b/core/types/block.go
index 1a2a1f2bd..1dae87962 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -62,14 +62,14 @@ func (n BlockNonce) Uint64() uint64 {
 	return binary.BigEndian.Uint64(n[:])
 }
 
-// MarshalJSON implements json.Marshaler
-func (n BlockNonce) MarshalJSON() ([]byte, error) {
-	return hexutil.Bytes(n[:]).MarshalJSON()
+// MarshalText encodes n as a hex string with 0x prefix.
+func (n BlockNonce) MarshalText() ([]byte, error) {
+	return hexutil.Bytes(n[:]).MarshalText()
 }
 
-// UnmarshalJSON implements json.Unmarshaler
-func (n *BlockNonce) UnmarshalJSON(input []byte) error {
-	return hexutil.UnmarshalJSON("BlockNonce", input, n[:])
+// UnmarshalText implements encoding.TextUnmarshaler.
+func (n *BlockNonce) UnmarshalText(input []byte) error {
+	return hexutil.UnmarshalFixedText("BlockNonce", input, n[:])
 }
 
 // Header represents a block header in the Ethereum blockchain.
diff --git a/core/types/bloom9.go b/core/types/bloom9.go
index 2a37b5977..60aacc301 100644
--- a/core/types/bloom9.go
+++ b/core/types/bloom9.go
@@ -75,14 +75,14 @@ func (b Bloom) TestBytes(test []byte) bool {
 
 }
 
-// MarshalJSON encodes b as a hex string with 0x prefix.
-func (b Bloom) MarshalJSON() ([]byte, error) {
-	return hexutil.Bytes(b[:]).MarshalJSON()
+// MarshalText encodes b as a hex string with 0x prefix.
+func (b Bloom) MarshalText() ([]byte, error) {
+	return hexutil.Bytes(b[:]).MarshalText()
 }
 
-// UnmarshalJSON b as a hex string with 0x prefix.
-func (b *Bloom) UnmarshalJSON(input []byte) error {
-	return hexutil.UnmarshalJSON("Bloom", input, b[:])
+// UnmarshalText b as a hex string with 0x prefix.
+func (b *Bloom) UnmarshalText(input []byte) error {
+	return hexutil.UnmarshalFixedText("Bloom", input, b[:])
 }
 
 func CreateBloom(receipts Receipts) Bloom {