This repository has been archived by the owner on Jan 10, 2024. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 119
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Add support to fuzz from go-fuzz input (#35)
* Add NewFromGoFuzz Add a helper function that enables using gofuzz (this project) with go-fuzz (https://github.com/dvyukov/go-fuzz) for continuose fuzzing. Essentially, it enables translating the fuzzing bytes from go-fuzz to any Go object using this library. This change will enable using this project with fuzzing websites such as fuzzit.dev or fuzzbuzz.io. The underlying implementation was an idea of lavalamp, by which a random source is created that generates random numbers from the input bytes slice. In this way changes in the source result in logical changes in the random data, which enables the fuzzer to efficiently search the space of inputs. Fixes #33
- Loading branch information
Showing
5 changed files
with
251 additions
and
0 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,81 @@ | ||
/* | ||
Copyright 2014 Google Inc. All rights reserved. | ||
Licensed under the Apache License, Version 2.0 (the "License"); | ||
you may not use this file except in compliance with the License. | ||
You may obtain a copy of the License at | ||
http://www.apache.org/licenses/LICENSE-2.0 | ||
Unless required by applicable law or agreed to in writing, software | ||
distributed under the License is distributed on an "AS IS" BASIS, | ||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
See the License for the specific language governing permissions and | ||
limitations under the License. | ||
*/ | ||
|
||
// Package bytesource provides a rand.Source64 that is determined by a slice of bytes. | ||
package bytesource | ||
|
||
import ( | ||
"bytes" | ||
"encoding/binary" | ||
"io" | ||
"math/rand" | ||
) | ||
|
||
// ByteSource implements rand.Source64 determined by a slice of bytes. The random numbers are | ||
// generated from each 8 bytes in the slice, until the last bytes are consumed, from which a | ||
// fallback pseudo random source is created in case more random numbers are required. | ||
// It also exposes a `bytes.Reader` API, which lets callers consume the bytes directly. | ||
type ByteSource struct { | ||
*bytes.Reader | ||
fallback rand.Source | ||
} | ||
|
||
// New returns a new ByteSource from a given slice of bytes. | ||
func New(input []byte) *ByteSource { | ||
s := &ByteSource{ | ||
Reader: bytes.NewReader(input), | ||
fallback: rand.NewSource(0), | ||
} | ||
if len(input) > 0 { | ||
s.fallback = rand.NewSource(int64(s.consumeUint64())) | ||
} | ||
return s | ||
} | ||
|
||
func (s *ByteSource) Uint64() uint64 { | ||
// Return from input if it was not exhausted. | ||
if s.Len() > 0 { | ||
return s.consumeUint64() | ||
} | ||
|
||
// Input was exhausted, return random number from fallback (in this case fallback should not be | ||
// nil). Try first having a Uint64 output (Should work in current rand implementation), | ||
// otherwise return a conversion of Int63. | ||
if s64, ok := s.fallback.(rand.Source64); ok { | ||
return s64.Uint64() | ||
} | ||
return uint64(s.fallback.Int63()) | ||
} | ||
|
||
func (s *ByteSource) Int63() int64 { | ||
return int64(s.Uint64() >> 1) | ||
} | ||
|
||
func (s *ByteSource) Seed(seed int64) { | ||
s.fallback = rand.NewSource(seed) | ||
s.Reader = bytes.NewReader(nil) | ||
} | ||
|
||
// consumeUint64 reads 8 bytes from the input and convert them to a uint64. It assumes that the the | ||
// bytes reader is not empty. | ||
func (s *ByteSource) consumeUint64() uint64 { | ||
var bytes [8]byte | ||
_, err := s.Read(bytes[:]) | ||
if err != nil && err != io.EOF { | ||
panic("failed reading source") // Should not happen. | ||
} | ||
return binary.BigEndian.Uint64(bytes[:]) | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,109 @@ | ||
/* | ||
Copyright 2014 Google Inc. All rights reserved. | ||
Licensed under the Apache License, Version 2.0 (the "License"); | ||
you may not use this file except in compliance with the License. | ||
You may obtain a copy of the License at | ||
http://www.apache.org/licenses/LICENSE-2.0 | ||
Unless required by applicable law or agreed to in writing, software | ||
distributed under the License is distributed on an "AS IS" BASIS, | ||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
See the License for the specific language governing permissions and | ||
limitations under the License. | ||
*/ | ||
package bytesource | ||
|
||
import ( | ||
"math/rand" | ||
"testing" | ||
) | ||
|
||
func TestByteSource(t *testing.T) { | ||
t.Parallel() | ||
|
||
randFromSource := func(s ...byte) *rand.Rand { | ||
return rand.New(New(s)) | ||
} | ||
|
||
randFromSeed := func(seed int64) *rand.Rand { | ||
var s1 ByteSource | ||
s1.Seed(seed) | ||
return rand.New(&s1) | ||
} | ||
|
||
t.Run("Inputs with identical 8 byte prefix", func(t *testing.T) { | ||
rand1 := randFromSource(1, 2, 3, 4, 5, 6, 7, 8, 9) | ||
rand2 := randFromSource(1, 2, 3, 4, 5, 6, 7, 8, 9) | ||
if rand1.Int() != rand2.Int() { | ||
t.Errorf("Inputs with identical 9 byte prefix result in different 1st output.") | ||
} | ||
if rand1.Int() != rand2.Int() { | ||
t.Errorf("Inputs with identical 9 byte prefix result in different 2nd output.") | ||
} | ||
}) | ||
|
||
t.Run("Inputs with different 8 byte prefix", func(t *testing.T) { | ||
rand2 := randFromSource(1, 2, 3, 4, 5, 6, 7, 1, 9) | ||
rand1 := randFromSource(1, 2, 3, 4, 5, 6, 7, 8, 9) | ||
if rand1.Int() != rand2.Int() { | ||
t.Errorf("Inputs with identical 9th byte prefix result in different 1st output.") | ||
} | ||
if rand1.Int() == rand2.Int() { | ||
t.Errorf("Inputs with different 8 bytes prefix result in identical 2nd output.") | ||
} | ||
}) | ||
|
||
t.Run("Multiple invocation", func(t *testing.T) { | ||
// First random from input byte, second from random source. | ||
r := randFromSource(1, 2, 3, 4, 6, 7, 8, 9) | ||
if r.Int() == r.Int() { | ||
t.Errorf("Two random numbers are identical.") | ||
} | ||
// First and second numbers from random source. | ||
r = randFromSource(1) | ||
if r.Int() == r.Int() { | ||
t.Errorf("Two random numbers are identical.") | ||
} | ||
}) | ||
|
||
t.Run("Seed", func(t *testing.T) { | ||
if randFromSeed(42).Int() != randFromSeed(42).Int() { | ||
t.Error("Two random numbers from the same seed differ.") | ||
} | ||
if randFromSeed(42).Int() == randFromSeed(43).Int() { | ||
t.Error("Two random numbers from different seeds are identical.") | ||
} | ||
}) | ||
} | ||
|
||
func TestByteSourceValues(t *testing.T) { | ||
t.Parallel() | ||
|
||
// Data in chunks of 8 bytes. | ||
data := []byte{ | ||
99, 12, 23, 12, 65, 34, 12, 12, | ||
99, 12, 23, 12, 25, 34, 15, 13, | ||
99, 12, 23, 42, 25, 34, 11, 14, | ||
99, 12, 54, 12, 25, 34, 99, 11, | ||
} | ||
|
||
r := rand.New(New(data)) | ||
|
||
got := []int{r.Int(), r.Int(), r.Int(), r.Int(), r.Int()} | ||
|
||
want := []int{ | ||
3568552425102051206, | ||
3568552489526560135, | ||
3568569467532292485, | ||
7616166771204380295, | ||
5210010188159375967, | ||
} | ||
|
||
for i := range got { | ||
if want[i] != got[i] { | ||
t.Errorf("want[%d] = %d, got: %d", i, want[i], got[i]) | ||
} | ||
} | ||
} |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters