Adding upstream version 1.17.13.upstream/1.17.13upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 747 insertions, 0 deletions

diff --git a/src/encoding/asn1/marshal.go b/src/encoding/asn1/marshal.go
new file mode 100644
index 0000000..5b4d786
--- /dev/null
+++ b/src/encoding/asn1/marshal.go
@@ -0,0 +1,747 @@
+// Copyright 2009 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 asn1
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"math/big"
+	"reflect"
+	"sort"
+	"time"
+	"unicode/utf8"
+)
+
+var (
+	byte00Encoder encoder = byteEncoder(0x00)
+	byteFFEncoder encoder = byteEncoder(0xff)
+)
+
+// encoder represents an ASN.1 element that is waiting to be marshaled.
+type encoder interface {
+	// Len returns the number of bytes needed to marshal this element.
+	Len() int
+	// Encode encodes this element by writing Len() bytes to dst.
+	Encode(dst []byte)
+}
+
+type byteEncoder byte
+
+func (c byteEncoder) Len() int {
+	return 1
+}
+
+func (c byteEncoder) Encode(dst []byte) {
+	dst[0] = byte(c)
+}
+
+type bytesEncoder []byte
+
+func (b bytesEncoder) Len() int {
+	return len(b)
+}
+
+func (b bytesEncoder) Encode(dst []byte) {
+	if copy(dst, b) != len(b) {
+		panic("internal error")
+	}
+}
+
+type stringEncoder string
+
+func (s stringEncoder) Len() int {
+	return len(s)
+}
+
+func (s stringEncoder) Encode(dst []byte) {
+	if copy(dst, s) != len(s) {
+		panic("internal error")
+	}
+}
+
+type multiEncoder []encoder
+
+func (m multiEncoder) Len() int {
+	var size int
+	for _, e := range m {
+		size += e.Len()
+	}
+	return size
+}
+
+func (m multiEncoder) Encode(dst []byte) {
+	var off int
+	for _, e := range m {
+		e.Encode(dst[off:])
+		off += e.Len()
+	}
+}
+
+type setEncoder []encoder
+
+func (s setEncoder) Len() int {
+	var size int
+	for _, e := range s {
+		size += e.Len()
+	}
+	return size
+}
+
+func (s setEncoder) Encode(dst []byte) {
+	// Per X690 Section 11.6: The encodings of the component values of a
+	// set-of value shall appear in ascending order, the encodings being
+	// compared as octet strings with the shorter components being padded
+	// at their trailing end with 0-octets.
+	//
+	// First we encode each element to its TLV encoding and then use
+	// octetSort to get the ordering expected by X690 DER rules before
+	// writing the sorted encodings out to dst.
+	l := make([][]byte, len(s))
+	for i, e := range s {
+		l[i] = make([]byte, e.Len())
+		e.Encode(l[i])
+	}
+
+	sort.Slice(l, func(i, j int) bool {
+		// Since we are using bytes.Compare to compare TLV encodings we
+		// don't need to right pad s[i] and s[j] to the same length as
+		// suggested in X690. If len(s[i]) < len(s[j]) the length octet of
+		// s[i], which is the first determining byte, will inherently be
+		// smaller than the length octet of s[j]. This lets us skip the
+		// padding step.
+		return bytes.Compare(l[i], l[j]) < 0
+	})
+
+	var off int
+	for _, b := range l {
+		copy(dst[off:], b)
+		off += len(b)
+	}
+}
+
+type taggedEncoder struct {
+	// scratch contains temporary space for encoding the tag and length of
+	// an element in order to avoid extra allocations.
+	scratch [8]byte
+	tag     encoder
+	body    encoder
+}
+
+func (t *taggedEncoder) Len() int {
+	return t.tag.Len() + t.body.Len()
+}
+
+func (t *taggedEncoder) Encode(dst []byte) {
+	t.tag.Encode(dst)
+	t.body.Encode(dst[t.tag.Len():])
+}
+
+type int64Encoder int64
+
+func (i int64Encoder) Len() int {
+	n := 1
+
+	for i > 127 {
+		n++
+		i >>= 8
+	}
+
+	for i < -128 {
+		n++
+		i >>= 8
+	}
+
+	return n
+}
+
+func (i int64Encoder) Encode(dst []byte) {
+	n := i.Len()
+
+	for j := 0; j < n; j++ {
+		dst[j] = byte(i >> uint((n-1-j)*8))
+	}
+}
+
+func base128IntLength(n int64) int {
+	if n == 0 {
+		return 1
+	}
+
+	l := 0
+	for i := n; i > 0; i >>= 7 {
+		l++
+	}
+
+	return l
+}
+
+func appendBase128Int(dst []byte, n int64) []byte {
+	l := base128IntLength(n)
+
+	for i := l - 1; i >= 0; i-- {
+		o := byte(n >> uint(i*7))
+		o &= 0x7f
+		if i != 0 {
+			o |= 0x80
+		}
+
+		dst = append(dst, o)
+	}
+
+	return dst
+}
+
+func makeBigInt(n *big.Int) (encoder, error) {
+	if n == nil {
+		return nil, StructuralError{"empty integer"}
+	}
+
+	if n.Sign() < 0 {
+		// A negative number has to be converted to two's-complement
+		// form. So we'll invert and subtract 1. If the
+		// most-significant-bit isn't set then we'll need to pad the
+		// beginning with 0xff in order to keep the number negative.
+		nMinus1 := new(big.Int).Neg(n)
+		nMinus1.Sub(nMinus1, bigOne)
+		bytes := nMinus1.Bytes()
+		for i := range bytes {
+			bytes[i] ^= 0xff
+		}
+		if len(bytes) == 0 || bytes[0]&0x80 == 0 {
+			return multiEncoder([]encoder{byteFFEncoder, bytesEncoder(bytes)}), nil
+		}
+		return bytesEncoder(bytes), nil
+	} else if n.Sign() == 0 {
+		// Zero is written as a single 0 zero rather than no bytes.
+		return byte00Encoder, nil
+	} else {
+		bytes := n.Bytes()
+		if len(bytes) > 0 && bytes[0]&0x80 != 0 {
+			// We'll have to pad this with 0x00 in order to stop it
+			// looking like a negative number.
+			return multiEncoder([]encoder{byte00Encoder, bytesEncoder(bytes)}), nil
+		}
+		return bytesEncoder(bytes), nil
+	}
+}
+
+func appendLength(dst []byte, i int) []byte {
+	n := lengthLength(i)
+
+	for ; n > 0; n-- {
+		dst = append(dst, byte(i>>uint((n-1)*8)))
+	}
+
+	return dst
+}
+
+func lengthLength(i int) (numBytes int) {
+	numBytes = 1
+	for i > 255 {
+		numBytes++
+		i >>= 8
+	}
+	return
+}
+
+func appendTagAndLength(dst []byte, t tagAndLength) []byte {
+	b := uint8(t.class) << 6
+	if t.isCompound {
+		b |= 0x20
+	}
+	if t.tag >= 31 {
+		b |= 0x1f
+		dst = append(dst, b)
+		dst = appendBase128Int(dst, int64(t.tag))
+	} else {
+		b |= uint8(t.tag)
+		dst = append(dst, b)
+	}
+
+	if t.length >= 128 {
+		l := lengthLength(t.length)
+		dst = append(dst, 0x80|byte(l))
+		dst = appendLength(dst, t.length)
+	} else {
+		dst = append(dst, byte(t.length))
+	}
+
+	return dst
+}
+
+type bitStringEncoder BitString
+
+func (b bitStringEncoder) Len() int {
+	return len(b.Bytes) + 1
+}
+
+func (b bitStringEncoder) Encode(dst []byte) {
+	dst[0] = byte((8 - b.BitLength%8) % 8)
+	if copy(dst[1:], b.Bytes) != len(b.Bytes) {
+		panic("internal error")
+	}
+}
+
+type oidEncoder []int
+
+func (oid oidEncoder) Len() int {
+	l := base128IntLength(int64(oid[0]*40 + oid[1]))
+	for i := 2; i < len(oid); i++ {
+		l += base128IntLength(int64(oid[i]))
+	}
+	return l
+}
+
+func (oid oidEncoder) Encode(dst []byte) {
+	dst = appendBase128Int(dst[:0], int64(oid[0]*40+oid[1]))
+	for i := 2; i < len(oid); i++ {
+		dst = appendBase128Int(dst, int64(oid[i]))
+	}
+}
+
+func makeObjectIdentifier(oid []int) (e encoder, err error) {
+	if len(oid) < 2 || oid[0] > 2 || (oid[0] < 2 && oid[1] >= 40) {
+		return nil, StructuralError{"invalid object identifier"}
+	}
+
+	return oidEncoder(oid), nil
+}
+
+func makePrintableString(s string) (e encoder, err error) {
+	for i := 0; i < len(s); i++ {
+		// The asterisk is often used in PrintableString, even though
+		// it is invalid. If a PrintableString was specifically
+		// requested then the asterisk is permitted by this code.
+		// Ampersand is allowed in parsing due a handful of CA
+		// certificates, however when making new certificates
+		// it is rejected.
+		if !isPrintable(s[i], allowAsterisk, rejectAmpersand) {
+			return nil, StructuralError{"PrintableString contains invalid character"}
+		}
+	}
+
+	return stringEncoder(s), nil
+}
+
+func makeIA5String(s string) (e encoder, err error) {
+	for i := 0; i < len(s); i++ {
+		if s[i] > 127 {
+			return nil, StructuralError{"IA5String contains invalid character"}
+		}
+	}
+
+	return stringEncoder(s), nil
+}
+
+func makeNumericString(s string) (e encoder, err error) {
+	for i := 0; i < len(s); i++ {
+		if !isNumeric(s[i]) {
+			return nil, StructuralError{"NumericString contains invalid character"}
+		}
+	}
+
+	return stringEncoder(s), nil
+}
+
+func makeUTF8String(s string) encoder {
+	return stringEncoder(s)
+}
+
+func appendTwoDigits(dst []byte, v int) []byte {
+	return append(dst, byte('0'+(v/10)%10), byte('0'+v%10))
+}
+
+func appendFourDigits(dst []byte, v int) []byte {
+	var bytes [4]byte
+	for i := range bytes {
+		bytes[3-i] = '0' + byte(v%10)
+		v /= 10
+	}
+	return append(dst, bytes[:]...)
+}
+
+func outsideUTCRange(t time.Time) bool {
+	year := t.Year()
+	return year < 1950 || year >= 2050
+}
+
+func makeUTCTime(t time.Time) (e encoder, err error) {
+	dst := make([]byte, 0, 18)
+
+	dst, err = appendUTCTime(dst, t)
+	if err != nil {
+		return nil, err
+	}
+
+	return bytesEncoder(dst), nil
+}
+
+func makeGeneralizedTime(t time.Time) (e encoder, err error) {
+	dst := make([]byte, 0, 20)
+
+	dst, err = appendGeneralizedTime(dst, t)
+	if err != nil {
+		return nil, err
+	}
+
+	return bytesEncoder(dst), nil
+}
+
+func appendUTCTime(dst []byte, t time.Time) (ret []byte, err error) {
+	year := t.Year()
+
+	switch {
+	case 1950 <= year && year < 2000:
+		dst = appendTwoDigits(dst, year-1900)
+	case 2000 <= year && year < 2050:
+		dst = appendTwoDigits(dst, year-2000)
+	default:
+		return nil, StructuralError{"cannot represent time as UTCTime"}
+	}
+
+	return appendTimeCommon(dst, t), nil
+}
+
+func appendGeneralizedTime(dst []byte, t time.Time) (ret []byte, err error) {
+	year := t.Year()
+	if year < 0 || year > 9999 {
+		return nil, StructuralError{"cannot represent time as GeneralizedTime"}
+	}
+
+	dst = appendFourDigits(dst, year)
+
+	return appendTimeCommon(dst, t), nil
+}
+
+func appendTimeCommon(dst []byte, t time.Time) []byte {
+	_, month, day := t.Date()
+
+	dst = appendTwoDigits(dst, int(month))
+	dst = appendTwoDigits(dst, day)
+
+	hour, min, sec := t.Clock()
+
+	dst = appendTwoDigits(dst, hour)
+	dst = appendTwoDigits(dst, min)
+	dst = appendTwoDigits(dst, sec)
+
+	_, offset := t.Zone()
+
+	switch {
+	case offset/60 == 0:
+		return append(dst, 'Z')
+	case offset > 0:
+		dst = append(dst, '+')
+	case offset < 0:
+		dst = append(dst, '-')
+	}
+
+	offsetMinutes := offset / 60
+	if offsetMinutes < 0 {
+		offsetMinutes = -offsetMinutes
+	}
+
+	dst = appendTwoDigits(dst, offsetMinutes/60)
+	dst = appendTwoDigits(dst, offsetMinutes%60)
+
+	return dst
+}
+
+func stripTagAndLength(in []byte) []byte {
+	_, offset, err := parseTagAndLength(in, 0)
+	if err != nil {
+		return in
+	}
+	return in[offset:]
+}
+
+func makeBody(value reflect.Value, params fieldParameters) (e encoder, err error) {
+	switch value.Type() {
+	case flagType:
+		return bytesEncoder(nil), nil
+	case timeType:
+		t := value.Interface().(time.Time)
+		if params.timeType == TagGeneralizedTime || outsideUTCRange(t) {
+			return makeGeneralizedTime(t)
+		}
+		return makeUTCTime(t)
+	case bitStringType:
+		return bitStringEncoder(value.Interface().(BitString)), nil
+	case objectIdentifierType:
+		return makeObjectIdentifier(value.Interface().(ObjectIdentifier))
+	case bigIntType:
+		return makeBigInt(value.Interface().(*big.Int))
+	}
+
+	switch v := value; v.Kind() {
+	case reflect.Bool:
+		if v.Bool() {
+			return byteFFEncoder, nil
+		}
+		return byte00Encoder, nil
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		return int64Encoder(v.Int()), nil
+	case reflect.Struct:
+		t := v.Type()
+
+		for i := 0; i < t.NumField(); i++ {
+			if !t.Field(i).IsExported() {
+				return nil, StructuralError{"struct contains unexported fields"}
+			}
+		}
+
+		startingField := 0
+
+		n := t.NumField()
+		if n == 0 {
+			return bytesEncoder(nil), nil
+		}
+
+		// If the first element of the structure is a non-empty
+		// RawContents, then we don't bother serializing the rest.
+		if t.Field(0).Type == rawContentsType {
+			s := v.Field(0)
+			if s.Len() > 0 {
+				bytes := s.Bytes()
+				/* The RawContents will contain the tag and
+				 * length fields but we'll also be writing
+				 * those ourselves, so we strip them out of
+				 * bytes */
+				return bytesEncoder(stripTagAndLength(bytes)), nil
+			}
+
+			startingField = 1
+		}
+
+		switch n1 := n - startingField; n1 {
+		case 0:
+			return bytesEncoder(nil), nil
+		case 1:
+			return makeField(v.Field(startingField), parseFieldParameters(t.Field(startingField).Tag.Get("asn1")))
+		default:
+			m := make([]encoder, n1)
+			for i := 0; i < n1; i++ {
+				m[i], err = makeField(v.Field(i+startingField), parseFieldParameters(t.Field(i+startingField).Tag.Get("asn1")))
+				if err != nil {
+					return nil, err
+				}
+			}
+
+			return multiEncoder(m), nil
+		}
+	case reflect.Slice:
+		sliceType := v.Type()
+		if sliceType.Elem().Kind() == reflect.Uint8 {
+			return bytesEncoder(v.Bytes()), nil
+		}
+
+		var fp fieldParameters
+
+		switch l := v.Len(); l {
+		case 0:
+			return bytesEncoder(nil), nil
+		case 1:
+			return makeField(v.Index(0), fp)
+		default:
+			m := make([]encoder, l)
+
+			for i := 0; i < l; i++ {
+				m[i], err = makeField(v.Index(i), fp)
+				if err != nil {
+					return nil, err
+				}
+			}
+
+			if params.set {
+				return setEncoder(m), nil
+			}
+			return multiEncoder(m), nil
+		}
+	case reflect.String:
+		switch params.stringType {
+		case TagIA5String:
+			return makeIA5String(v.String())
+		case TagPrintableString:
+			return makePrintableString(v.String())
+		case TagNumericString:
+			return makeNumericString(v.String())
+		default:
+			return makeUTF8String(v.String()), nil
+		}
+	}
+
+	return nil, StructuralError{"unknown Go type"}
+}
+
+func makeField(v reflect.Value, params fieldParameters) (e encoder, err error) {
+	if !v.IsValid() {
+		return nil, fmt.Errorf("asn1: cannot marshal nil value")
+	}
+	// If the field is an interface{} then recurse into it.
+	if v.Kind() == reflect.Interface && v.Type().NumMethod() == 0 {
+		return makeField(v.Elem(), params)
+	}
+
+	if v.Kind() == reflect.Slice && v.Len() == 0 && params.omitEmpty {
+		return bytesEncoder(nil), nil
+	}
+
+	if params.optional && params.defaultValue != nil && canHaveDefaultValue(v.Kind()) {
+		defaultValue := reflect.New(v.Type()).Elem()
+		defaultValue.SetInt(*params.defaultValue)
+
+		if reflect.DeepEqual(v.Interface(), defaultValue.Interface()) {
+			return bytesEncoder(nil), nil
+		}
+	}
+
+	// If no default value is given then the zero value for the type is
+	// assumed to be the default value. This isn't obviously the correct
+	// behavior, but it's what Go has traditionally done.
+	if params.optional && params.defaultValue == nil {
+		if reflect.DeepEqual(v.Interface(), reflect.Zero(v.Type()).Interface()) {
+			return bytesEncoder(nil), nil
+		}
+	}
+
+	if v.Type() == rawValueType {
+		rv := v.Interface().(RawValue)
+		if len(rv.FullBytes) != 0 {
+			return bytesEncoder(rv.FullBytes), nil
+		}
+
+		t := new(taggedEncoder)
+
+		t.tag = bytesEncoder(appendTagAndLength(t.scratch[:0], tagAndLength{rv.Class, rv.Tag, len(rv.Bytes), rv.IsCompound}))
+		t.body = bytesEncoder(rv.Bytes)
+
+		return t, nil
+	}
+
+	matchAny, tag, isCompound, ok := getUniversalType(v.Type())
+	if !ok || matchAny {
+		return nil, StructuralError{fmt.Sprintf("unknown Go type: %v", v.Type())}
+	}
+
+	if params.timeType != 0 && tag != TagUTCTime {
+		return nil, StructuralError{"explicit time type given to non-time member"}
+	}
+
+	if params.stringType != 0 && tag != TagPrintableString {
+		return nil, StructuralError{"explicit string type given to non-string member"}
+	}
+
+	switch tag {
+	case TagPrintableString:
+		if params.stringType == 0 {
+			// This is a string without an explicit string type. We'll use
+			// a PrintableString if the character set in the string is
+			// sufficiently limited, otherwise we'll use a UTF8String.
+			for _, r := range v.String() {
+				if r >= utf8.RuneSelf || !isPrintable(byte(r), rejectAsterisk, rejectAmpersand) {
+					if !utf8.ValidString(v.String()) {
+						return nil, errors.New("asn1: string not valid UTF-8")
+					}
+					tag = TagUTF8String
+					break
+				}
+			}
+		} else {
+			tag = params.stringType
+		}
+	case TagUTCTime:
+		if params.timeType == TagGeneralizedTime || outsideUTCRange(v.Interface().(time.Time)) {
+			tag = TagGeneralizedTime
+		}
+	}
+
+	if params.set {
+		if tag != TagSequence {
+			return nil, StructuralError{"non sequence tagged as set"}
+		}
+		tag = TagSet
+	}
+
+	// makeField can be called for a slice that should be treated as a SET
+	// but doesn't have params.set set, for instance when using a slice
+	// with the SET type name suffix. In this case getUniversalType returns
+	// TagSet, but makeBody doesn't know about that so will treat the slice
+	// as a sequence. To work around this we set params.set.
+	if tag == TagSet && !params.set {
+		params.set = true
+	}
+
+	t := new(taggedEncoder)
+
+	t.body, err = makeBody(v, params)
+	if err != nil {
+		return nil, err
+	}
+
+	bodyLen := t.body.Len()
+
+	class := ClassUniversal
+	if params.tag != nil {
+		if params.application {
+			class = ClassApplication
+		} else if params.private {
+			class = ClassPrivate
+		} else {
+			class = ClassContextSpecific
+		}
+
+		if params.explicit {
+			t.tag = bytesEncoder(appendTagAndLength(t.scratch[:0], tagAndLength{ClassUniversal, tag, bodyLen, isCompound}))
+
+			tt := new(taggedEncoder)
+
+			tt.body = t
+
+			tt.tag = bytesEncoder(appendTagAndLength(tt.scratch[:0], tagAndLength{
+				class:      class,
+				tag:        *params.tag,
+				length:     bodyLen + t.tag.Len(),
+				isCompound: true,
+			}))
+
+			return tt, nil
+		}
+
+		// implicit tag.
+		tag = *params.tag
+	}
+
+	t.tag = bytesEncoder(appendTagAndLength(t.scratch[:0], tagAndLength{class, tag, bodyLen, isCompound}))
+
+	return t, nil
+}
+
+// Marshal returns the ASN.1 encoding of val.
+//
+// In addition to the struct tags recognised by Unmarshal, the following can be
+// used:
+//
+//	ia5:         causes strings to be marshaled as ASN.1, IA5String values
+//	omitempty:   causes empty slices to be skipped
+//	printable:   causes strings to be marshaled as ASN.1, PrintableString values
+//	utf8:        causes strings to be marshaled as ASN.1, UTF8String values
+//	utc:         causes time.Time to be marshaled as ASN.1, UTCTime values
+//	generalized: causes time.Time to be marshaled as ASN.1, GeneralizedTime values
+func Marshal(val interface{}) ([]byte, error) {
+	return MarshalWithParams(val, "")
+}
+
+// MarshalWithParams allows field parameters to be specified for the
+// top-level element. The form of the params is the same as the field tags.
+func MarshalWithParams(val interface{}, params string) ([]byte, error) {
+	e, err := makeField(reflect.ValueOf(val), parseFieldParameters(params))
+	if err != nil {
+		return nil, err
+	}
+	b := make([]byte, e.Len())
+	e.Encode(b)
+	return b, nil
+}