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// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package multipart
import (
"bytes"
"fmt"
"io"
"math"
"net/textproto"
"os"
"strings"
"testing"
)
func TestReadForm(t *testing.T) {
b := strings.NewReader(strings.ReplaceAll(message, "\n", "\r\n"))
r := NewReader(b, boundary)
f, err := r.ReadForm(25)
if err != nil {
t.Fatal("ReadForm:", err)
}
defer f.RemoveAll()
if g, e := f.Value["texta"][0], textaValue; g != e {
t.Errorf("texta value = %q, want %q", g, e)
}
if g, e := f.Value["textb"][0], textbValue; g != e {
t.Errorf("texta value = %q, want %q", g, e)
}
fd := testFile(t, f.File["filea"][0], "filea.txt", fileaContents)
if _, ok := fd.(*os.File); ok {
t.Error("file is *os.File, should not be")
}
fd.Close()
fd = testFile(t, f.File["fileb"][0], "fileb.txt", filebContents)
if _, ok := fd.(*os.File); !ok {
t.Errorf("file has unexpected underlying type %T", fd)
}
fd.Close()
}
func TestReadFormWithNamelessFile(t *testing.T) {
b := strings.NewReader(strings.ReplaceAll(messageWithFileWithoutName, "\n", "\r\n"))
r := NewReader(b, boundary)
f, err := r.ReadForm(25)
if err != nil {
t.Fatal("ReadForm:", err)
}
defer f.RemoveAll()
if g, e := f.Value["hiddenfile"][0], filebContents; g != e {
t.Errorf("hiddenfile value = %q, want %q", g, e)
}
}
// Issue 40430: Handle ReadForm(math.MaxInt64)
func TestReadFormMaxMemoryOverflow(t *testing.T) {
b := strings.NewReader(strings.ReplaceAll(messageWithTextContentType, "\n", "\r\n"))
r := NewReader(b, boundary)
f, err := r.ReadForm(math.MaxInt64)
if err != nil {
t.Fatalf("ReadForm(MaxInt64): %v", err)
}
if f == nil {
t.Fatal("ReadForm(MaxInt64): missing form")
}
}
func TestReadFormWithTextContentType(t *testing.T) {
// From https://github.com/golang/go/issues/24041
b := strings.NewReader(strings.ReplaceAll(messageWithTextContentType, "\n", "\r\n"))
r := NewReader(b, boundary)
f, err := r.ReadForm(25)
if err != nil {
t.Fatal("ReadForm:", err)
}
defer f.RemoveAll()
if g, e := f.Value["texta"][0], textaValue; g != e {
t.Errorf("texta value = %q, want %q", g, e)
}
}
func testFile(t *testing.T, fh *FileHeader, efn, econtent string) File {
if fh.Filename != efn {
t.Errorf("filename = %q, want %q", fh.Filename, efn)
}
if fh.Size != int64(len(econtent)) {
t.Errorf("size = %d, want %d", fh.Size, len(econtent))
}
f, err := fh.Open()
if err != nil {
t.Fatal("opening file:", err)
}
b := new(strings.Builder)
_, err = io.Copy(b, f)
if err != nil {
t.Fatal("copying contents:", err)
}
if g := b.String(); g != econtent {
t.Errorf("contents = %q, want %q", g, econtent)
}
return f
}
const (
fileaContents = "This is a test file."
filebContents = "Another test file."
textaValue = "foo"
textbValue = "bar"
boundary = `MyBoundary`
)
const messageWithFileWithoutName = `
--MyBoundary
Content-Disposition: form-data; name="hiddenfile"; filename=""
Content-Type: text/plain
` + filebContents + `
--MyBoundary--
`
const messageWithTextContentType = `
--MyBoundary
Content-Disposition: form-data; name="texta"
Content-Type: text/plain
` + textaValue + `
--MyBoundary
`
const message = `
--MyBoundary
Content-Disposition: form-data; name="filea"; filename="filea.txt"
Content-Type: text/plain
` + fileaContents + `
--MyBoundary
Content-Disposition: form-data; name="fileb"; filename="fileb.txt"
Content-Type: text/plain
` + filebContents + `
--MyBoundary
Content-Disposition: form-data; name="texta"
` + textaValue + `
--MyBoundary
Content-Disposition: form-data; name="textb"
` + textbValue + `
--MyBoundary--
`
func TestReadForm_NoReadAfterEOF(t *testing.T) {
maxMemory := int64(32) << 20
boundary := `---------------------------8d345eef0d38dc9`
body := `
-----------------------------8d345eef0d38dc9
Content-Disposition: form-data; name="version"
171
-----------------------------8d345eef0d38dc9--`
mr := NewReader(&failOnReadAfterErrorReader{t: t, r: strings.NewReader(body)}, boundary)
f, err := mr.ReadForm(maxMemory)
if err != nil {
t.Fatal(err)
}
t.Logf("Got: %#v", f)
}
// failOnReadAfterErrorReader is an io.Reader wrapping r.
// It fails t if any Read is called after a failing Read.
type failOnReadAfterErrorReader struct {
t *testing.T
r io.Reader
sawErr error
}
func (r *failOnReadAfterErrorReader) Read(p []byte) (n int, err error) {
if r.sawErr != nil {
r.t.Fatalf("unexpected Read on Reader after previous read saw error %v", r.sawErr)
}
n, err = r.r.Read(p)
r.sawErr = err
return
}
// TestReadForm_NonFileMaxMemory asserts that the ReadForm maxMemory limit is applied
// while processing non-file form data as well as file form data.
func TestReadForm_NonFileMaxMemory(t *testing.T) {
if testing.Short() {
t.Skip("skipping in -short mode")
}
n := 10 << 20
largeTextValue := strings.Repeat("1", n)
message := `--MyBoundary
Content-Disposition: form-data; name="largetext"
` + largeTextValue + `
--MyBoundary--
`
testBody := strings.ReplaceAll(message, "\n", "\r\n")
// Try parsing the form with increasing maxMemory values.
// Changes in how we account for non-file form data may cause the exact point
// where we change from rejecting the form as too large to accepting it to vary,
// but we should see both successes and failures.
const failWhenMaxMemoryLessThan = 128
for maxMemory := int64(0); maxMemory < failWhenMaxMemoryLessThan*2; maxMemory += 16 {
b := strings.NewReader(testBody)
r := NewReader(b, boundary)
f, err := r.ReadForm(maxMemory)
if err != nil {
continue
}
if g := f.Value["largetext"][0]; g != largeTextValue {
t.Errorf("largetext mismatch: got size: %v, expected size: %v", len(g), len(largeTextValue))
}
f.RemoveAll()
if maxMemory < failWhenMaxMemoryLessThan {
t.Errorf("ReadForm(%v): no error, expect to hit memory limit when maxMemory < %v", maxMemory, failWhenMaxMemoryLessThan)
}
return
}
t.Errorf("ReadForm(x) failed for x < 1024, expect success")
}
// TestReadForm_MetadataTooLarge verifies that we account for the size of field names,
// MIME headers, and map entry overhead while limiting the memory consumption of parsed forms.
func TestReadForm_MetadataTooLarge(t *testing.T) {
for _, test := range []struct {
name string
f func(*Writer)
}{{
name: "large name",
f: func(fw *Writer) {
name := strings.Repeat("a", 10<<20)
w, _ := fw.CreateFormField(name)
w.Write([]byte("value"))
},
}, {
name: "large MIME header",
f: func(fw *Writer) {
h := make(textproto.MIMEHeader)
h.Set("Content-Disposition", `form-data; name="a"`)
h.Set("X-Foo", strings.Repeat("a", 10<<20))
w, _ := fw.CreatePart(h)
w.Write([]byte("value"))
},
}, {
name: "many parts",
f: func(fw *Writer) {
for i := 0; i < 110000; i++ {
w, _ := fw.CreateFormField("f")
w.Write([]byte("v"))
}
},
}} {
t.Run(test.name, func(t *testing.T) {
var buf bytes.Buffer
fw := NewWriter(&buf)
test.f(fw)
if err := fw.Close(); err != nil {
t.Fatal(err)
}
fr := NewReader(&buf, fw.Boundary())
_, err := fr.ReadForm(0)
if err != ErrMessageTooLarge {
t.Errorf("fr.ReadForm() = %v, want ErrMessageTooLarge", err)
}
})
}
}
// TestReadForm_ManyFiles_Combined tests that a multipart form containing many files only
// results in a single on-disk file.
func TestReadForm_ManyFiles_Combined(t *testing.T) {
const distinct = false
testReadFormManyFiles(t, distinct)
}
// TestReadForm_ManyFiles_Distinct tests that setting GODEBUG=multipartfiles=distinct
// results in every file in a multipart form being placed in a distinct on-disk file.
func TestReadForm_ManyFiles_Distinct(t *testing.T) {
t.Setenv("GODEBUG", "multipartfiles=distinct")
const distinct = true
testReadFormManyFiles(t, distinct)
}
func testReadFormManyFiles(t *testing.T, distinct bool) {
var buf bytes.Buffer
fw := NewWriter(&buf)
const numFiles = 10
for i := 0; i < numFiles; i++ {
name := fmt.Sprint(i)
w, err := fw.CreateFormFile(name, name)
if err != nil {
t.Fatal(err)
}
w.Write([]byte(name))
}
if err := fw.Close(); err != nil {
t.Fatal(err)
}
fr := NewReader(&buf, fw.Boundary())
fr.tempDir = t.TempDir()
form, err := fr.ReadForm(0)
if err != nil {
t.Fatal(err)
}
for i := 0; i < numFiles; i++ {
name := fmt.Sprint(i)
if got := len(form.File[name]); got != 1 {
t.Fatalf("form.File[%q] has %v entries, want 1", name, got)
}
fh := form.File[name][0]
file, err := fh.Open()
if err != nil {
t.Fatalf("form.File[%q].Open() = %v", name, err)
}
if distinct {
if _, ok := file.(*os.File); !ok {
t.Fatalf("form.File[%q].Open: %T, want *os.File", name, file)
}
}
got, err := io.ReadAll(file)
file.Close()
if string(got) != name || err != nil {
t.Fatalf("read form.File[%q]: %q, %v; want %q, nil", name, string(got), err, name)
}
}
dir, err := os.Open(fr.tempDir)
if err != nil {
t.Fatal(err)
}
defer dir.Close()
names, err := dir.Readdirnames(0)
if err != nil {
t.Fatal(err)
}
wantNames := 1
if distinct {
wantNames = numFiles
}
if len(names) != wantNames {
t.Fatalf("temp dir contains %v files; want 1", len(names))
}
if err := form.RemoveAll(); err != nil {
t.Fatalf("form.RemoveAll() = %v", err)
}
names, err = dir.Readdirnames(0)
if err != nil {
t.Fatal(err)
}
if len(names) != 0 {
t.Fatalf("temp dir contains %v files; want 0", len(names))
}
}
func TestReadFormLimits(t *testing.T) {
for _, test := range []struct {
values int
files int
extraKeysPerFile int
wantErr error
godebug string
}{
{values: 1000},
{values: 1001, wantErr: ErrMessageTooLarge},
{values: 500, files: 500},
{values: 501, files: 500, wantErr: ErrMessageTooLarge},
{files: 1000},
{files: 1001, wantErr: ErrMessageTooLarge},
{files: 1, extraKeysPerFile: 9998}, // plus Content-Disposition and Content-Type
{files: 1, extraKeysPerFile: 10000, wantErr: ErrMessageTooLarge},
{godebug: "multipartmaxparts=100", values: 100},
{godebug: "multipartmaxparts=100", values: 101, wantErr: ErrMessageTooLarge},
{godebug: "multipartmaxheaders=100", files: 2, extraKeysPerFile: 48},
{godebug: "multipartmaxheaders=100", files: 2, extraKeysPerFile: 50, wantErr: ErrMessageTooLarge},
} {
name := fmt.Sprintf("values=%v/files=%v/extraKeysPerFile=%v", test.values, test.files, test.extraKeysPerFile)
if test.godebug != "" {
name += fmt.Sprintf("/godebug=%v", test.godebug)
}
t.Run(name, func(t *testing.T) {
if test.godebug != "" {
t.Setenv("GODEBUG", test.godebug)
}
var buf bytes.Buffer
fw := NewWriter(&buf)
for i := 0; i < test.values; i++ {
w, _ := fw.CreateFormField(fmt.Sprintf("field%v", i))
fmt.Fprintf(w, "value %v", i)
}
for i := 0; i < test.files; i++ {
h := make(textproto.MIMEHeader)
h.Set("Content-Disposition",
fmt.Sprintf(`form-data; name="file%v"; filename="file%v"`, i, i))
h.Set("Content-Type", "application/octet-stream")
for j := 0; j < test.extraKeysPerFile; j++ {
h.Set(fmt.Sprintf("k%v", j), "v")
}
w, _ := fw.CreatePart(h)
fmt.Fprintf(w, "value %v", i)
}
if err := fw.Close(); err != nil {
t.Fatal(err)
}
fr := NewReader(bytes.NewReader(buf.Bytes()), fw.Boundary())
form, err := fr.ReadForm(1 << 10)
if err == nil {
defer form.RemoveAll()
}
if err != test.wantErr {
t.Errorf("ReadForm = %v, want %v", err, test.wantErr)
}
})
}
}
func BenchmarkReadForm(b *testing.B) {
for _, test := range []struct {
name string
form func(fw *Writer, count int)
}{{
name: "fields",
form: func(fw *Writer, count int) {
for i := 0; i < count; i++ {
w, _ := fw.CreateFormField(fmt.Sprintf("field%v", i))
fmt.Fprintf(w, "value %v", i)
}
},
}, {
name: "files",
form: func(fw *Writer, count int) {
for i := 0; i < count; i++ {
w, _ := fw.CreateFormFile(fmt.Sprintf("field%v", i), fmt.Sprintf("file%v", i))
fmt.Fprintf(w, "value %v", i)
}
},
}} {
b.Run(test.name, func(b *testing.B) {
for _, maxMemory := range []int64{
0,
1 << 20,
} {
var buf bytes.Buffer
fw := NewWriter(&buf)
test.form(fw, 10)
if err := fw.Close(); err != nil {
b.Fatal(err)
}
b.Run(fmt.Sprintf("maxMemory=%v", maxMemory), func(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
fr := NewReader(bytes.NewReader(buf.Bytes()), fw.Boundary())
form, err := fr.ReadForm(maxMemory)
if err != nil {
b.Fatal(err)
}
form.RemoveAll()
}
})
}
})
}
}
|