garble/testdata/script/reflect.txtar

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

! binsubstr main$exe 'garble_main.go' 'test/main' 'importedpkg.','IndirectObfuscated' 'IndirectNamedWithoutReflect' 'AliasIndirectNamedWithReflect' 'AliasIndirectNamedWithoutReflect' 'FmtTypeField' 'LocalObfuscated'
binsubstr main$exe 'ReflectInDefined' 'ExportedField2' 'unexportedField2' 'IndirectUnobfuscated' 'IndirectNamedWithReflect' 'ForeignNamedType' 'DownstreamField' 'SiblingField'

[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 1.23
-- garble_main.go --
package main

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

	"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))
	fmt.Println(reflect.TypeOf(importedpkg2.ForeignNamedType{}).Name())

	// 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.
	_ = genericRenderTemplate("name: {{.Name}} value: {{.Value}} port: {{.Port}}", GenericTemplateData{
		Name:  "test",
		Value: "example",
		Port:  8080,
	})
	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{
		DownstreamField: "downstream",
	})

	// An edge case; the struct type is defined in package importedpkg2.
	// importedpkg uses reflect.TypeOf on ReflectInDefined, which embeds
	// ReflectInSiblingImport, so all reachable fields (including SiblingField)
	// must keep real names for reflection
	sibling := importedpkg2.ReflectInSiblingImport{
		SiblingField: "sibling",
	}
	st := reflect.TypeOf(sibling)
	sf2 := reflect.ValueOf(sibling).Field(0)
	fmt.Printf("%s:%q\n", st.Field(0).Name, sf2.String())

	// Foreign generic wrapper (cf. cloudflare-go param.Field): all fields reachable
	// from reflect.TypeOf must keep real names, including for dynamic FieldByName.
	wrapped := importedpkg2.FieldByNameWrapper[string]{Value: "wrapped", Present: true}
	wt := reflect.TypeOf(wrapped)
	for _, name := range []string{"Value", "Present"} {
		sf, ok := wt.FieldByName(name)
		if !ok {
			panic("FieldByNameWrapper missing field " + name)
		}
		if sf.Name != name {
			panic("unexpected StructField name")
		}
	}
	dynField := "Value"
	sf, ok := wt.FieldByName(dynField)
	if !ok || sf.Type.Kind() != reflect.String {
		panic("dynamic FieldByName on wrapper failed")
	}
	fmt.Printf("wrapper: %v %v\n",
		reflect.ValueOf(wrapped).FieldByName("Value").Interface(),
		reflect.ValueOf(wrapped).FieldByName("Present").Bool(),
	)

	// 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 }{})

	// reflection can see all type names, even local ones, so they cannot be obfuscated.
	{
		type TypeOfNamedField struct{ NamedReflectionField int }
		type TypeOfEmbeddedField struct{ EmbeddedReflectionField int }
		type TypeOfParent struct {
			ReflectionField TypeOfNamedField
			TypeOfEmbeddedField
		}
		t := reflect.TypeOf(TypeOfParent{})
		fmt.Println("TypeOfParent's own name:", t.Name())
		namedField, _ := t.FieldByName("ReflectionField")
		namedFieldField, _ := namedField.Type.FieldByName("NamedReflectionField")
		fmt.Println("TypeOfParent named:",
			namedField.Type.Name(),
			namedFieldField.Name,
		)
		embedField, _ := t.FieldByName("TypeOfEmbeddedField")
		embedFieldField, _ := embedField.Type.FieldByName("EmbeddedReflectionField")
		fmt.Println("TypeOfParent embedded:",
			embedField.Type.Name(),
			embedFieldField.Name,
		)
	}

	y := UnnamedStructFields{}
	y.unexportedGoGoProto = new(struct {
		mu           sync.Mutex
		extensionMap map[int32]EncodingT
	})

	fmt.Println(reflect.TypeOf(Connection{}))
}

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 GenericTemplateData struct {
	Name  string
	Value string
	Port  int
}

func genericRenderTemplate[T any](src string, data T) error {
	tmpl, err := template.New("").Parse(src)
	if err != nil {
		return err
	}
	return tmpl.Execute(os.Stdout, data)
}

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 pingMsg struct {
	Data string `sshtype:"192"`
}

type pongMsg struct {
	Data string `sshtype:"193"`
}

// golang.org/x/crypto/ssh converts a reflected type to another type
func testSSH() {
	var msg = pingMsg{
		Data: "data",
	}
	json.Marshal(msg)

	_ = pongMsg(msg)
}

// variations similar to ssh
type reflectedMsg struct {
	Data string
}

type convertedMsg struct {
	Data string
}

func reflectConvert() {
	msg := reflectedMsg(convertedMsg{})
	json.Marshal(msg)
}

type reflectedMsg2 struct {
	Data string
}

type convertedMsg2 struct {
	Data string
}

func unrelatedConvert() {
	// only discoverable by rechecking the package
	_ = convertedMsg2(reflectedMsg2{})
}

func reflectUnrelatedConv() {
	var msg = reflectedMsg2{
		Data: "data",
	}
	json.Marshal(msg)

}

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 })
}

// Some projects declare types with unnamed struct fields,
// and the entire type is used via reflection and cannot be obfuscated.
// However, when assigning to these fields, the use of inline anonymous struct types
// confused garble, and it did not obfuscate those inline structs as well.
// That resulted in "cannot use X as Y value in assignment" build errors.

var _ = reflect.TypeOf(UnnamedStructFields{})

type UnnamedStructFields struct {
	// As seen in github.com/gogo/protobuf/proto.
	unexportedGoGoProto *struct {
		mu           sync.Mutex
		extensionMap map[int32]EncodingT
	}
}

func gobStruct() {
	type gobAlias struct {
		Security []map[string]struct {
			List []string
			Pad  bool
		}
	}
	alias := gobAlias{}

	gob.NewEncoder(os.Stdout).Encode(alias)

	alias.Security = make([]map[string]struct {
		List []string
		Pad  bool
	}, 0, len([]string{}))
}

func gobMap() {
	type gobAlias struct {
		Security map[string]struct {
			List []string
			Pad  bool
		}
	}
	alias := gobAlias{}

	gob.NewEncoder(os.Stdout).Encode(alias)

	alias.Security = make(map[string]struct {
		List []string
		Pad  bool
	}, len([]string{}))
}

func gobChan() {
	type gobAlias struct {
		Security chan struct {
			List []string
			Pad  bool
		}
	}

	alias := gobAlias{}

	gob.NewEncoder(os.Stdout).Encode(alias)

	alias.Security = make(chan struct {
		List []string
		Pad  bool
	}, len([]string{}))
}

type Connection struct {
	MaxLen struct {
		Varchar int
	}
}

// NewConnection create a new connection from databaseURL string
func NewConnection() *Connection {
	return &Connection{
		MaxLen: struct {
			Varchar int
		}{
			Varchar: 0x7FFF,
		},
	}
}

func closure() {
	type gobAlias struct {
		Security func() struct {
			Pad bool
		}
	}

	alias := gobAlias{}

	gob.NewEncoder(os.Stdout).Encode(alias)

	outer := func() func() struct{ Pad bool } {
		return func() struct{ Pad bool } {
			return struct{ Pad bool }{Pad: true}
		}
	}

	alias.Security = outer()
}

-- 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 {
	DownstreamField 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 {
	SiblingField string
}

type ForeignNamedType struct{}

// FieldByNameWrapper is a generic struct in another package; callers may use
// reflect.FieldByName (including with a non-constant name) on values of this type.
type FieldByNameWrapper[T any] struct {
	Value   T
	Present bool
}

-- 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
ForeignNamedType
ReflectValueOf{ExportedField:"abc", unexportedField:""}
[method: abc]
{"Foo":3}
Hello Dave.
name: test value: example port: 8080
{"InnerField":3,"Anon":{"AnonField":0}}
struct { DownstreamField string }{DownstreamField:"downstream"}
SiblingField:"sibling"
wrapper: wrapped true
{{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 }
TypeOfParent's own name: TypeOfParent
TypeOfParent named: TypeOfNamedField NamedReflectionField
TypeOfParent embedded: TypeOfEmbeddedField EmbeddedReflectionField
main.Connection