garble/testdata/script/reflect.txtar

exec garble build
exec ./main
cmp stdout main.stdout

! binsubstr main$exe 'garble_main.go' 'test/main' 'importedpkg.' 'DownstreamObfuscated' 'SiblingObfuscated' 'IndirectObfuscated' 'IndirectNamedWithoutReflect' 'AliasIndirectNamedWithReflect' 'AliasIndirectNamedWithoutReflect' 'FmtTypeField' 'LocalObfuscated'
binsubstr main$exe 'ReflectInDefined' 'ExportedField2' 'unexportedField2' 'IndirectUnobfuscated' 'IndirectNamedWithReflect'

[short] stop # no need to verify this with -short

# Check that the program works as expected without garble.
go build
exec ./main
cmp stdout main.stdout
-- go.mod --
module test/main

go 1.20
-- garble_main.go --
package main

import (
	"crypto/ecdsa"
	"crypto/elliptic"
	"crypto/rand"
	"crypto/x509"
	"crypto/x509/pkix"
	"encoding/json"
	"fmt"
	"math/big"
	"os"
	"reflect"
	"unsafe"
	"strings"
	"text/template"

	"test/main/importedpkg"
	"test/main/importedpkg2"
)

var Sink interface{}

func main() {
	// Fields still work fine when they are not obfuscated.
	fmt.Println(importedpkg.ReflectInDefinedVar.ExportedField2)
	fmt.Println(importedpkg.ReflectInDefined{ExportedField2: 5})

	// Type names are not obfuscated either, when reflection is used.
	printfWithoutPackage("%T\n", importedpkg.ReflectTypeOf(2))
	printfWithoutPackage("%T\n", importedpkg.ReflectTypeOfIndirect(4))

	// More complex use of reflect.
	v := importedpkg.ReflectValueOfVar
	printfWithoutPackage("%#v\n", v)
	method := reflect.ValueOf(&v).MethodByName("ExportedMethodName")
	if method.IsValid() {
		fmt.Println(method.Call(nil))
	} else {
		fmt.Println("method not found")
	}

	// Use of a common library using reflect, encoding/json.
	enc, _ := json.Marshal(EncodingT{Foo: 3})
	fmt.Println(string(enc))

	// Another common library, text/template.
	tmpl := template.Must(template.New("").Parse("Hello {{.Name}}."))
	_ = tmpl.Execute(os.Stdout, struct{Name string}{Name: "Dave"})
	fmt.Println() // Always print a newline.

	// Another complex case, involving embedding and another package.
	outer := &importedpkg.EmbeddingOuter{}
	outer.InnerField = 3
	enc, _ = json.Marshal(outer)
	fmt.Println(string(enc))

	// An edge case; the struct type is defined in a different package.
	// Note that the struct type is unnamed, but it still has named fields.
	// We only use reflection on it here, not the declaring package.
	// As such, we should obfuscate the field name.
	// Simply using the field name here used to cause build failures.
	_ = reflect.TypeOf(importedpkg.UnnamedWithDownstreamReflect{})
	fmt.Printf("%v\n", importedpkg.UnnamedWithDownstreamReflect{
		DownstreamObfuscated: "downstream",
	})

	// An edge case; the struct type is defined in package importedpkg2.
	// importedpkg2 does not use reflection on it, so it's not obfuscated there.
	// importedpkg uses reflection on a type containing ReflectInSiblingImport.
	// If our logic is incorrect, we might inconsistently obfuscate the type.
	// We should not obfuscate it when building any package.
	fmt.Printf("%v\n", importedpkg2.ReflectInSiblingImport{
		SiblingObfuscated: "sibling",
	})

	// Using type aliases as both regular fields, and embedded fields.
	var emb EmbeddingIndirect
	emb.With.IndirectUnobfuscated = "indirect-with"
	emb.With.DuplicateFieldName = 3
	emb.Without.IndirectObfuscated = "indirect-without"
	emb.Without.DuplicateFieldName = 4
	fmt.Printf("%v\n", emb)
	printfWithoutPackage("%#v\n", emb.With)

	// TODO: don't obfuscate the embedded field name here
	// printfWithoutPackage("%#v\n", importedpkg.ReflectEmbeddingAlias{})

	indirectReflection(IndirectReflection{})
	fmt.Println(FmtType{})

	// Variadic functions are a bit tricky as the number of parameters is variable.
	// We want to notice indirect uses of reflection via all variadic arguments.
	_ = importedpkg.VariadicReflect(0, 1, 2, 3)
	_ = importedpkg.VariadicReflect(0)
	variadic := VariadicReflection{ReflectionField: "variadic"}
	_ = importedpkg.VariadicReflect("foo", 1, variadic, false)
	printfWithoutPackage("%#v\n", variadic)

	testx509()
	testGoSpew()

	// Very complex reflection used by gorm
	user := StatUser{}
	find(&user)

	// Similar to gorm with composite literals instead of direct assignments
	userComp := StatCompUser{}
	findComp(&userComp)

	x := UnnamedStructInterface(importedpkg.ReflectUnnamedStruct(0))
	x.UnnamedStructMethod(struct{ UnnamedStructField string }{UnnamedStructField: "field value"})

	// Local names not used in reflection should not be in the final binary,
	// even if they are embedded in a struct and become a field name.
	type unexportedLocalObfuscated struct { LocalObfuscatedA int }
	type ExportedLocalObfuscated struct { LocalObfuscatedB int }
	type EmbeddingObfuscated struct {
		unexportedLocalObfuscated
		ExportedLocalObfuscated
	}
	// Ensure the types are kept in the binary. Use an anonymous type too.
	_ = fmt.Sprintf("%#v", EmbeddingObfuscated{})
	_ = fmt.Sprintf("%#v", struct{ExportedLocalObfuscated}{})
}

type EmbeddingIndirect struct {
	// With field names, to test selectors above.
	With importedpkg.AliasIndirectNamedWithReflect
	Without importedpkg.AliasIndirectNamedWithoutReflect

	// Embedding used to crash garble, too.
	importedpkg.AliasIndirectNamedWithReflect
}

func printfWithoutPackage(format string, v any) {
	s := fmt.Sprintf(format, v)
	if _, without, found := strings.Cut(s, "."); found {
		s = without
	}
	fmt.Print(s)
}

type EncodingT struct {
	Foo int
}

type RecursiveStruct struct {
	*RecursiveStruct
	list []RecursiveStruct
}

// This could crash or hang if we don't deal with loops.
var _ = reflect.TypeOf(RecursiveStruct{})

type IndirectReflection struct {
	ReflectionField string
}

func indirectReflection(v any) {
	fmt.Println(reflect.TypeOf(v).Field(0).Name)
}

type VariadicReflection struct {
	ReflectionField string
}

type FmtType struct {
	FmtTypeField int
}

// copied from github.com/davecgh/go-spew, which reaches into reflect's internals
func testGoSpew() {
	flagValOffset := func() uintptr {
		field, ok := reflect.TypeOf(reflect.Value{}).FieldByName("flag")
		if !ok {
			panic("reflect.Value has no flag field")
		}
		return field.Offset
	}()

	type flag uintptr
	flagField := func(v *reflect.Value) *flag {
		return (*flag)(unsafe.Pointer(uintptr(unsafe.Pointer(v)) + flagValOffset))
	}

	type t0 int
	var t struct {
		A t0
		t0
		a t0
	}
	vA := reflect.ValueOf(t).FieldByName("A")
	va := reflect.ValueOf(t).FieldByName("a")
	vt0 := reflect.ValueOf(t).FieldByName("t0")
	flagvA := *flagField(&vA)
	flagva := *flagField(&va)
	flagvt0 := *flagField(&vt0)

	if flagvA&flagva&flagvt0 == 0 {
		panic("reflect.Value read-only flag has changed semantics")
	}

	type T0 int
	var T struct {
		A T0
		T0
		a T0
	}
	vA = reflect.ValueOf(T).FieldByName("A")
	va = reflect.ValueOf(T).FieldByName("a")
	vt0 = reflect.ValueOf(T).FieldByName("T0")
	flagvA = *flagField(&vA)
	flagva = *flagField(&va)
	flagvt0 = *flagField(&vt0)

	if flagvA&flagva&flagvt0 == 0 {
		panic("reflect.Value read-only flag has changed semantics")
	}
}

// encoding/x509 uses encoding/asn1, which uses reflect.
// In one place it depends on field names; that used to be broken by garble.
func testx509() {
	priv, err := ecdsa.GenerateKey(elliptic.P521(), rand.Reader)
	if err != nil {
		panic(err)
	}

	template := x509.Certificate{
		SerialNumber: big.NewInt(1),
		Subject:      pkix.Name{Organization: []string{"Acme Co"}},
	}

	derBytes, err := x509.CreateCertificate(rand.Reader, &template, &template, &priv.PublicKey, priv)
	if err != nil {
		panic(err)
	}

	_, err = x509.ParseCertificate(derBytes)
	if err != nil {
		panic(err)
	}
}


type StatUser struct {
	Id      int64 `gorm:"primaryKey"`
	User_Id int64
}

type StatCompUser struct {
	Id      int64 `gorm:"primaryKey"`
	User_Id int64
}

type Transaction struct {
	Statement Statement
}

type Statement struct {
	Dest  interface{}
	Model string
}

func find(dest interface{}) {
	tx := Transaction{}

	tx.Statement.Dest = dest
	execute(tx)
}

func findComp(dest interface{}) {
	tx := Transaction{
		Statement: Statement{
			Dest: dest,
		},
	}

	execute(tx)
}

func execute(db Transaction) {
	stmt := db.Statement

	v := reflect.TypeOf(stmt.Dest)

	fmt.Println(v)
}

type UnnamedStructInterface interface {
	UnnamedStructMethod(struct{ UnnamedStructField string })
}


-- importedpkg/imported.go --
package importedpkg

import (
	"fmt"
	"reflect"

	"test/main/importedpkg/indirect"
	"test/main/importedpkg2"
)

type ReflectTypeOf int

var _ = reflect.TypeOf(ReflectTypeOf(0))

type ReflectTypeOfIndirect int

var _ = reflect.TypeOf(new([]*ReflectTypeOfIndirect))

type ReflectValueOf struct {
	ExportedField string

	unexportedField string
}

func (r *ReflectValueOf) ExportedMethodName() string { return "method: " + r.ExportedField }

var ReflectValueOfVar = ReflectValueOf{ExportedField: "abc"}

var _ = reflect.TypeOf(ReflectValueOfVar)

type ReflectInDefined struct {
	ExportedField2 int

	unexportedField2 int

	importedpkg2.ReflectInSiblingImport
}

var ReflectInDefinedVar = ReflectInDefined{ExportedField2: 9000}

var _ = reflect.TypeOf(ReflectInDefinedVar)

var _ = reflect.TypeOf([]*struct{EmbeddingOuter}{})

type EmbeddingOuter struct {
	EmbeddingInner
	Anon struct {
		AnonField int
	}
}

type EmbeddingInner struct {
	InnerField int
}

type UnnamedWithDownstreamReflect = struct {
	DownstreamObfuscated string
}

type (
	AliasIndirectNamedWithReflect = indirect.IndirectNamedWithReflect
	AliasIndirectNamedWithoutReflect = indirect.IndirectNamedWithoutReflect
)

var _ = reflect.TypeOf(ReflectEmbeddingAlias{})

type ReflectEmbeddingAlias struct {
	ReflectEmbeddedAlias
}

type ReflectEmbeddedAlias = ReflectEmbeddingNamed

type ReflectEmbeddingNamed struct{}

func VariadicReflect(x any, ys ...any) int {
	_ = reflect.TypeOf(x)

	for _, y := range ys {
		_ = reflect.TypeOf(y)
	}

	return len(ys)
}

type ReflectUnnamedStruct int

func (ReflectUnnamedStruct) UnnamedStructMethod(s struct{ UnnamedStructField string }) {
	fmt.Println(reflect.TypeOf(s))
}

-- importedpkg2/imported2.go --
package importedpkg2

type ReflectInSiblingImport struct {
	SiblingObfuscated string
}

-- importedpkg/indirect/indirect.go --
package indirect

import "reflect"

var _ = reflect.TypeOf(IndirectNamedWithReflect{})

type IndirectNamedWithReflect struct {
	IndirectUnobfuscated string

	DuplicateFieldName int
}

type IndirectNamedWithoutReflect struct {
	IndirectObfuscated string

	DuplicateFieldName int
}

-- main.stdout --
9000
{5 0 {}}
ReflectTypeOf
ReflectTypeOfIndirect
ReflectValueOf{ExportedField:"abc", unexportedField:""}
[method: abc]
{"Foo":3}
Hello Dave.
{"InnerField":3,"Anon":{"AnonField":0}}
{downstream}
{sibling}
{{indirect-with 3} {indirect-without 4} { 0}}
IndirectNamedWithReflect{IndirectUnobfuscated:"indirect-with", DuplicateFieldName:3}
ReflectionField
{0}
VariadicReflection{ReflectionField:"variadic"}
*main.StatUser
*main.StatCompUser
struct { UnnamedStructField string }