lbcd/txscript/stack_test.go
Dave Collins edc0d15882 txscript: Consensus audit.
This commit contains fixes from the results of a thorough audit of
txscript to find any cases of script evaluation which doesn't match the
required consensus behavior.  These conditions are fairly obscure and
highly unlikely to happen in any real scripts, but they could have
nevertheless been used by a clever attacker with malicious intent to
cause a fork.

Test cases which exercise these conditions have been added to the
reference tests and will contributed upstream to improve the quality for
the entire ecosystem.
2015-05-06 09:41:50 -05:00

993 lines
16 KiB
Go

// Copyright (c) 2013-2015 The btcsuite developers
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package txscript
import (
"bytes"
"errors"
"fmt"
"testing"
)
// TestStack tests that all of the stack operations work as expected.
func TestStack(t *testing.T) {
t.Parallel()
tests := []struct {
name string
before [][]byte
operation func(*stack) error
expectedReturn error
after [][]byte
}{
{
"noop",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
return nil
},
nil,
[][]byte{{1}, {2}, {3}, {4}, {5}},
},
{
"peek underflow (byte)",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
_, err := s.PeekByteArray(5)
return err
},
ErrStackUnderflow,
nil,
},
{
"peek underflow (int)",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
_, err := s.PeekInt(5)
return err
},
ErrStackUnderflow,
nil,
},
{
"peek underflow (bool)",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
_, err := s.PeekBool(5)
return err
},
ErrStackUnderflow,
nil,
},
{
"pop",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
val, err := s.PopByteArray()
if err != nil {
return err
}
if !bytes.Equal(val, []byte{5}) {
return errors.New("not equal")
}
return err
},
nil,
[][]byte{{1}, {2}, {3}, {4}},
},
{
"pop",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
val, err := s.PopByteArray()
if err != nil {
return err
}
if !bytes.Equal(val, []byte{5}) {
return errors.New("not equal")
}
return err
},
nil,
[][]byte{{1}, {2}, {3}, {4}},
},
{
"pop everything",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
for i := 0; i < 5; i++ {
_, err := s.PopByteArray()
if err != nil {
return err
}
}
return nil
},
nil,
nil,
},
{
"pop underflow",
[][]byte{{1}, {2}, {3}, {4}, {5}},
func(s *stack) error {
for i := 0; i < 6; i++ {
_, err := s.PopByteArray()
if err != nil {
return err
}
}
return nil
},
ErrStackUnderflow,
nil,
},
{
"pop bool",
[][]byte{nil},
func(s *stack) error {
val, err := s.PopBool()
if err != nil {
return err
}
if val != false {
return errors.New("unexpected value")
}
return nil
},
nil,
nil,
},
{
"pop bool",
[][]byte{{1}},
func(s *stack) error {
val, err := s.PopBool()
if err != nil {
return err
}
if val != true {
return errors.New("unexpected value")
}
return nil
},
nil,
nil,
},
{
"pop bool",
nil,
func(s *stack) error {
_, err := s.PopBool()
if err != nil {
return err
}
return nil
},
ErrStackUnderflow,
nil,
},
{
"popInt 0",
[][]byte{{0x0}},
func(s *stack) error {
v, err := s.PopInt()
if err != nil {
return err
}
if v != 0 {
return errors.New("0 != 0 on popInt")
}
return nil
},
nil,
nil,
},
{
"popInt -0",
[][]byte{{0x80}},
func(s *stack) error {
v, err := s.PopInt()
if err != nil {
return err
}
if v != 0 {
return errors.New("-0 != 0 on popInt")
}
return nil
},
nil,
nil,
},
{
"popInt 1",
[][]byte{{0x01}},
func(s *stack) error {
v, err := s.PopInt()
if err != nil {
return err
}
if v != 1 {
return errors.New("1 != 1 on popInt")
}
return nil
},
nil,
nil,
},
{
"popInt 1 leading 0",
[][]byte{{0x01, 0x00, 0x00, 0x00}},
func(s *stack) error {
v, err := s.PopInt()
if err != nil {
return err
}
if v != 1 {
fmt.Printf("%v != %v\n", v, 1)
return errors.New("1 != 1 on popInt")
}
return nil
},
nil,
nil,
},
{
"popInt -1",
[][]byte{{0x81}},
func(s *stack) error {
v, err := s.PopInt()
if err != nil {
return err
}
if v != -1 {
return errors.New("-1 != -1 on popInt")
}
return nil
},
nil,
nil,
},
{
"popInt -1 leading 0",
[][]byte{{0x01, 0x00, 0x00, 0x80}},
func(s *stack) error {
v, err := s.PopInt()
if err != nil {
return err
}
if v != -1 {
fmt.Printf("%v != %v\n", v, -1)
return errors.New("-1 != -1 on popInt")
}
return nil
},
nil,
nil,
},
// Triggers the multibyte case in asInt
{
"popInt -513",
[][]byte{{0x1, 0x82}},
func(s *stack) error {
v, err := s.PopInt()
if err != nil {
return err
}
if v != -513 {
fmt.Printf("%v != %v\n", v, -513)
return errors.New("1 != 1 on popInt")
}
return nil
},
nil,
nil,
},
// Confirm that the asInt code doesn't modify the base data.
{
"peekint nomodify -1",
[][]byte{{0x01, 0x00, 0x00, 0x80}},
func(s *stack) error {
v, err := s.PeekInt(0)
if err != nil {
return err
}
if v != -1 {
fmt.Printf("%v != %v\n", v, -1)
return errors.New("-1 != -1 on popInt")
}
return nil
},
nil,
[][]byte{{0x01, 0x00, 0x00, 0x80}},
},
{
"PushInt 0",
nil,
func(s *stack) error {
s.PushInt(scriptNum(0))
return nil
},
nil,
[][]byte{{}},
},
{
"PushInt 1",
nil,
func(s *stack) error {
s.PushInt(scriptNum(1))
return nil
},
nil,
[][]byte{{0x1}},
},
{
"PushInt -1",
nil,
func(s *stack) error {
s.PushInt(scriptNum(-1))
return nil
},
nil,
[][]byte{{0x81}},
},
{
"PushInt two bytes",
nil,
func(s *stack) error {
s.PushInt(scriptNum(256))
return nil
},
nil,
// little endian.. *sigh*
[][]byte{{0x00, 0x01}},
},
{
"PushInt leading zeros",
nil,
func(s *stack) error {
// this will have the highbit set
s.PushInt(scriptNum(128))
return nil
},
nil,
[][]byte{{0x80, 0x00}},
},
{
"dup",
[][]byte{{1}},
func(s *stack) error {
err := s.DupN(1)
if err != nil {
return err
}
return nil
},
nil,
[][]byte{{1}, {1}},
},
{
"dup2",
[][]byte{{1}, {2}},
func(s *stack) error {
err := s.DupN(2)
if err != nil {
return err
}
return nil
},
nil,
[][]byte{{1}, {2}, {1}, {2}},
},
{
"dup3",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
err := s.DupN(3)
if err != nil {
return err
}
return nil
},
nil,
[][]byte{{1}, {2}, {3}, {1}, {2}, {3}},
},
{
"dup0",
[][]byte{{1}},
func(s *stack) error {
err := s.DupN(0)
if err != nil {
return err
}
return nil
},
ErrStackInvalidArgs,
nil,
},
{
"dup-1",
[][]byte{{1}},
func(s *stack) error {
err := s.DupN(-1)
if err != nil {
return err
}
return nil
},
ErrStackInvalidArgs,
nil,
},
{
"dup too much",
[][]byte{{1}},
func(s *stack) error {
err := s.DupN(2)
if err != nil {
return err
}
return nil
},
ErrStackUnderflow,
nil,
},
{
"dup-1",
[][]byte{{1}},
func(s *stack) error {
err := s.DupN(-1)
if err != nil {
return err
}
return nil
},
ErrStackInvalidArgs,
nil,
},
{
"PushBool true",
nil,
func(s *stack) error {
s.PushBool(true)
return nil
},
nil,
[][]byte{{1}},
},
{
"PushBool false",
nil,
func(s *stack) error {
s.PushBool(false)
return nil
},
nil,
[][]byte{nil},
},
{
"PushBool PopBool",
nil,
func(s *stack) error {
s.PushBool(true)
val, err := s.PopBool()
if err != nil {
return err
}
if val != true {
return errors.New("unexpected value")
}
return nil
},
nil,
nil,
},
{
"PushBool PopBool 2",
nil,
func(s *stack) error {
s.PushBool(false)
val, err := s.PopBool()
if err != nil {
return err
}
if val != false {
return errors.New("unexpected value")
}
return nil
},
nil,
nil,
},
{
"PushInt PopBool",
nil,
func(s *stack) error {
s.PushInt(scriptNum(1))
val, err := s.PopBool()
if err != nil {
return err
}
if val != true {
return errors.New("unexpected value")
}
return nil
},
nil,
nil,
},
{
"PushInt PopBool 2",
nil,
func(s *stack) error {
s.PushInt(scriptNum(0))
val, err := s.PopBool()
if err != nil {
return err
}
if val != false {
return errors.New("unexpected value")
}
return nil
},
nil,
nil,
},
{
"PushInt PopBool 2",
nil,
func(s *stack) error {
s.PushInt(scriptNum(0))
val, err := s.PopBool()
if err != nil {
return err
}
if val != false {
return errors.New("unexpected value")
}
return nil
},
nil,
nil,
},
{
"Nip top",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
return s.NipN(0)
},
nil,
[][]byte{{1}, {2}},
},
{
"Nip middle",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
return s.NipN(1)
},
nil,
[][]byte{{1}, {3}},
},
{
"Nip low",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
return s.NipN(2)
},
nil,
[][]byte{{2}, {3}},
},
{
"Nip too much",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
// bite off more than we can chew
return s.NipN(3)
},
ErrStackUnderflow,
[][]byte{{2}, {3}},
},
{
"keep on tucking",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
return s.Tuck()
},
nil,
[][]byte{{1}, {3}, {2}, {3}},
},
{
"a little tucked up",
[][]byte{{1}}, // too few arguments for tuck
func(s *stack) error {
return s.Tuck()
},
ErrStackUnderflow,
nil,
},
{
"all tucked up",
nil, // too few arguments for tuck
func(s *stack) error {
return s.Tuck()
},
ErrStackUnderflow,
nil,
},
{
"drop 1",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.DropN(1)
},
nil,
[][]byte{{1}, {2}, {3}},
},
{
"drop 2",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.DropN(2)
},
nil,
[][]byte{{1}, {2}},
},
{
"drop 3",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.DropN(3)
},
nil,
[][]byte{{1}},
},
{
"drop 4",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.DropN(4)
},
nil,
nil,
},
{
"drop 4/5",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.DropN(5)
},
ErrStackUnderflow,
nil,
},
{
"drop invalid",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.DropN(0)
},
ErrStackInvalidArgs,
nil,
},
{
"Rot1",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.RotN(1)
},
nil,
[][]byte{{1}, {3}, {4}, {2}},
},
{
"Rot2",
[][]byte{{1}, {2}, {3}, {4}, {5}, {6}},
func(s *stack) error {
return s.RotN(2)
},
nil,
[][]byte{{3}, {4}, {5}, {6}, {1}, {2}},
},
{
"Rot too little",
[][]byte{{1}, {2}},
func(s *stack) error {
return s.RotN(1)
},
ErrStackUnderflow,
nil,
},
{
"Rot0",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
return s.RotN(0)
},
ErrStackInvalidArgs,
nil,
},
{
"Swap1",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.SwapN(1)
},
nil,
[][]byte{{1}, {2}, {4}, {3}},
},
{
"Swap2",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.SwapN(2)
},
nil,
[][]byte{{3}, {4}, {1}, {2}},
},
{
"Swap too little",
[][]byte{{1}},
func(s *stack) error {
return s.SwapN(1)
},
ErrStackUnderflow,
nil,
},
{
"Swap0",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
return s.SwapN(0)
},
ErrStackInvalidArgs,
nil,
},
{
"Over1",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.OverN(1)
},
nil,
[][]byte{{1}, {2}, {3}, {4}, {3}},
},
{
"Over2",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.OverN(2)
},
nil,
[][]byte{{1}, {2}, {3}, {4}, {1}, {2}},
},
{
"Over too little",
[][]byte{{1}},
func(s *stack) error {
return s.OverN(1)
},
ErrStackUnderflow,
nil,
},
{
"Over0",
[][]byte{{1}, {2}, {3}},
func(s *stack) error {
return s.OverN(0)
},
ErrStackInvalidArgs,
nil,
},
{
"Pick1",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.PickN(1)
},
nil,
[][]byte{{1}, {2}, {3}, {4}, {3}},
},
{
"Pick2",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.PickN(2)
},
nil,
[][]byte{{1}, {2}, {3}, {4}, {2}},
},
{
"Pick too little",
[][]byte{{1}},
func(s *stack) error {
return s.PickN(1)
},
ErrStackUnderflow,
nil,
},
{
"Roll1",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.RollN(1)
},
nil,
[][]byte{{1}, {2}, {4}, {3}},
},
{
"Roll2",
[][]byte{{1}, {2}, {3}, {4}},
func(s *stack) error {
return s.RollN(2)
},
nil,
[][]byte{{1}, {3}, {4}, {2}},
},
{
"Roll too little",
[][]byte{{1}},
func(s *stack) error {
return s.RollN(1)
},
ErrStackUnderflow,
nil,
},
{
"Peek bool",
[][]byte{{1}},
func(s *stack) error {
// Peek bool is otherwise pretty well tested,
// just check it works.
val, err := s.PeekBool(0)
if err != nil {
return err
}
if val != true {
return errors.New("invalid result")
}
return nil
},
nil,
[][]byte{{1}},
},
{
"Peek bool 2",
[][]byte{nil},
func(s *stack) error {
// Peek bool is otherwise pretty well tested,
// just check it works.
val, err := s.PeekBool(0)
if err != nil {
return err
}
if val != false {
return errors.New("invalid result")
}
return nil
},
nil,
[][]byte{nil},
},
{
"Peek int",
[][]byte{{1}},
func(s *stack) error {
// Peek int is otherwise pretty well tested,
// just check it works.
val, err := s.PeekInt(0)
if err != nil {
return err
}
if val != 1 {
return errors.New("invalid result")
}
return nil
},
nil,
[][]byte{{1}},
},
{
"Peek int 2",
[][]byte{{0}},
func(s *stack) error {
// Peek int is otherwise pretty well tested,
// just check it works.
val, err := s.PeekInt(0)
if err != nil {
return err
}
if val != 0 {
return errors.New("invalid result")
}
return nil
},
nil,
[][]byte{{0}},
},
{
"pop int",
nil,
func(s *stack) error {
s.PushInt(scriptNum(1))
// Peek int is otherwise pretty well tested,
// just check it works.
val, err := s.PopInt()
if err != nil {
return err
}
if val != 1 {
return errors.New("invalid result")
}
return nil
},
nil,
nil,
},
{
"pop empty",
nil,
func(s *stack) error {
// Peek int is otherwise pretty well tested,
// just check it works.
_, err := s.PopInt()
return err
},
ErrStackUnderflow,
nil,
},
}
for _, test := range tests {
s := stack{}
for i := range test.before {
s.PushByteArray(test.before[i])
}
err := test.operation(&s)
if err != test.expectedReturn {
t.Errorf("%s: operation return not what expected: %v "+
"vs %v", test.name, err, test.expectedReturn)
}
if err != nil {
continue
}
if int32(len(test.after)) != s.Depth() {
t.Errorf("%s: stack depth doesn't match expected: %v "+
"vs %v", test.name, len(test.after),
s.Depth())
}
for i := range test.after {
val, err := s.PeekByteArray(s.Depth() - int32(i) - 1)
if err != nil {
t.Errorf("%s: can't peek %dth stack entry: %v",
test.name, i, err)
break
}
if !bytes.Equal(val, test.after[i]) {
t.Errorf("%s: %dth stack entry doesn't match "+
"expected: %v vs %v", test.name, i, val,
test.after[i])
break
}
}
}
}