diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/cryptobyte/asn1.go')
-rw-r--r-- | vendor/golang.org/x/crypto/cryptobyte/asn1.go | 732 |
1 files changed, 0 insertions, 732 deletions
diff --git a/vendor/golang.org/x/crypto/cryptobyte/asn1.go b/vendor/golang.org/x/crypto/cryptobyte/asn1.go deleted file mode 100644 index 88ec8b4fb..000000000 --- a/vendor/golang.org/x/crypto/cryptobyte/asn1.go +++ /dev/null @@ -1,732 +0,0 @@ -// Copyright 2017 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 cryptobyte - -import ( - encoding_asn1 "encoding/asn1" - "fmt" - "math/big" - "reflect" - "time" - - "golang.org/x/crypto/cryptobyte/asn1" -) - -// This file contains ASN.1-related methods for String and Builder. - -// Builder - -// AddASN1Int64 appends a DER-encoded ASN.1 INTEGER. -func (b *Builder) AddASN1Int64(v int64) { - b.addASN1Signed(asn1.INTEGER, v) -} - -// AddASN1Enum appends a DER-encoded ASN.1 ENUMERATION. -func (b *Builder) AddASN1Enum(v int64) { - b.addASN1Signed(asn1.ENUM, v) -} - -func (b *Builder) addASN1Signed(tag asn1.Tag, v int64) { - b.AddASN1(tag, func(c *Builder) { - length := 1 - for i := v; i >= 0x80 || i < -0x80; i >>= 8 { - length++ - } - - for ; length > 0; length-- { - i := v >> uint((length-1)*8) & 0xff - c.AddUint8(uint8(i)) - } - }) -} - -// AddASN1Uint64 appends a DER-encoded ASN.1 INTEGER. -func (b *Builder) AddASN1Uint64(v uint64) { - b.AddASN1(asn1.INTEGER, func(c *Builder) { - length := 1 - for i := v; i >= 0x80; i >>= 8 { - length++ - } - - for ; length > 0; length-- { - i := v >> uint((length-1)*8) & 0xff - c.AddUint8(uint8(i)) - } - }) -} - -// AddASN1BigInt appends a DER-encoded ASN.1 INTEGER. -func (b *Builder) AddASN1BigInt(n *big.Int) { - if b.err != nil { - return - } - - b.AddASN1(asn1.INTEGER, func(c *Builder) { - if n.Sign() < 0 { - // A negative number has to be converted to two's-complement form. So we - // 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 bytes[0]&0x80 == 0 { - c.add(0xff) - } - c.add(bytes...) - } else if n.Sign() == 0 { - c.add(0) - } else { - bytes := n.Bytes() - if bytes[0]&0x80 != 0 { - c.add(0) - } - c.add(bytes...) - } - }) -} - -// AddASN1OctetString appends a DER-encoded ASN.1 OCTET STRING. -func (b *Builder) AddASN1OctetString(bytes []byte) { - b.AddASN1(asn1.OCTET_STRING, func(c *Builder) { - c.AddBytes(bytes) - }) -} - -const generalizedTimeFormatStr = "20060102150405Z0700" - -// AddASN1GeneralizedTime appends a DER-encoded ASN.1 GENERALIZEDTIME. -func (b *Builder) AddASN1GeneralizedTime(t time.Time) { - if t.Year() < 0 || t.Year() > 9999 { - b.err = fmt.Errorf("cryptobyte: cannot represent %v as a GeneralizedTime", t) - return - } - b.AddASN1(asn1.GeneralizedTime, func(c *Builder) { - c.AddBytes([]byte(t.Format(generalizedTimeFormatStr))) - }) -} - -// AddASN1BitString appends a DER-encoded ASN.1 BIT STRING. This does not -// support BIT STRINGs that are not a whole number of bytes. -func (b *Builder) AddASN1BitString(data []byte) { - b.AddASN1(asn1.BIT_STRING, func(b *Builder) { - b.AddUint8(0) - b.AddBytes(data) - }) -} - -func (b *Builder) addBase128Int(n int64) { - var length int - if n == 0 { - length = 1 - } else { - for i := n; i > 0; i >>= 7 { - length++ - } - } - - for i := length - 1; i >= 0; i-- { - o := byte(n >> uint(i*7)) - o &= 0x7f - if i != 0 { - o |= 0x80 - } - - b.add(o) - } -} - -func isValidOID(oid encoding_asn1.ObjectIdentifier) bool { - if len(oid) < 2 { - return false - } - - if oid[0] > 2 || (oid[0] <= 1 && oid[1] >= 40) { - return false - } - - for _, v := range oid { - if v < 0 { - return false - } - } - - return true -} - -func (b *Builder) AddASN1ObjectIdentifier(oid encoding_asn1.ObjectIdentifier) { - b.AddASN1(asn1.OBJECT_IDENTIFIER, func(b *Builder) { - if !isValidOID(oid) { - b.err = fmt.Errorf("cryptobyte: invalid OID: %v", oid) - return - } - - b.addBase128Int(int64(oid[0])*40 + int64(oid[1])) - for _, v := range oid[2:] { - b.addBase128Int(int64(v)) - } - }) -} - -func (b *Builder) AddASN1Boolean(v bool) { - b.AddASN1(asn1.BOOLEAN, func(b *Builder) { - if v { - b.AddUint8(0xff) - } else { - b.AddUint8(0) - } - }) -} - -func (b *Builder) AddASN1NULL() { - b.add(uint8(asn1.NULL), 0) -} - -// MarshalASN1 calls encoding_asn1.Marshal on its input and appends the result if -// successful or records an error if one occurred. -func (b *Builder) MarshalASN1(v interface{}) { - // NOTE(martinkr): This is somewhat of a hack to allow propagation of - // encoding_asn1.Marshal errors into Builder.err. N.B. if you call MarshalASN1 with a - // value embedded into a struct, its tag information is lost. - if b.err != nil { - return - } - bytes, err := encoding_asn1.Marshal(v) - if err != nil { - b.err = err - return - } - b.AddBytes(bytes) -} - -// AddASN1 appends an ASN.1 object. The object is prefixed with the given tag. -// Tags greater than 30 are not supported and result in an error (i.e. -// low-tag-number form only). The child builder passed to the -// BuilderContinuation can be used to build the content of the ASN.1 object. -func (b *Builder) AddASN1(tag asn1.Tag, f BuilderContinuation) { - if b.err != nil { - return - } - // Identifiers with the low five bits set indicate high-tag-number format - // (two or more octets), which we don't support. - if tag&0x1f == 0x1f { - b.err = fmt.Errorf("cryptobyte: high-tag number identifier octects not supported: 0x%x", tag) - return - } - b.AddUint8(uint8(tag)) - b.addLengthPrefixed(1, true, f) -} - -// String - -func (s *String) ReadASN1Boolean(out *bool) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.INTEGER) || len(bytes) != 1 { - return false - } - - switch bytes[0] { - case 0: - *out = false - case 0xff: - *out = true - default: - return false - } - - return true -} - -var bigIntType = reflect.TypeOf((*big.Int)(nil)).Elem() - -// ReadASN1Integer decodes an ASN.1 INTEGER into out and advances. If out does -// not point to an integer or to a big.Int, it panics. It returns true on -// success and false on error. -func (s *String) ReadASN1Integer(out interface{}) bool { - if reflect.TypeOf(out).Kind() != reflect.Ptr { - panic("out is not a pointer") - } - switch reflect.ValueOf(out).Elem().Kind() { - case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64: - var i int64 - if !s.readASN1Int64(&i) || reflect.ValueOf(out).Elem().OverflowInt(i) { - return false - } - reflect.ValueOf(out).Elem().SetInt(i) - return true - case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64: - var u uint64 - if !s.readASN1Uint64(&u) || reflect.ValueOf(out).Elem().OverflowUint(u) { - return false - } - reflect.ValueOf(out).Elem().SetUint(u) - return true - case reflect.Struct: - if reflect.TypeOf(out).Elem() == bigIntType { - return s.readASN1BigInt(out.(*big.Int)) - } - } - panic("out does not point to an integer type") -} - -func checkASN1Integer(bytes []byte) bool { - if len(bytes) == 0 { - // An INTEGER is encoded with at least one octet. - return false - } - if len(bytes) == 1 { - return true - } - if bytes[0] == 0 && bytes[1]&0x80 == 0 || bytes[0] == 0xff && bytes[1]&0x80 == 0x80 { - // Value is not minimally encoded. - return false - } - return true -} - -var bigOne = big.NewInt(1) - -func (s *String) readASN1BigInt(out *big.Int) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.INTEGER) || !checkASN1Integer(bytes) { - return false - } - if bytes[0]&0x80 == 0x80 { - // Negative number. - neg := make([]byte, len(bytes)) - for i, b := range bytes { - neg[i] = ^b - } - out.SetBytes(neg) - out.Add(out, bigOne) - out.Neg(out) - } else { - out.SetBytes(bytes) - } - return true -} - -func (s *String) readASN1Int64(out *int64) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.INTEGER) || !checkASN1Integer(bytes) || !asn1Signed(out, bytes) { - return false - } - return true -} - -func asn1Signed(out *int64, n []byte) bool { - length := len(n) - if length > 8 { - return false - } - for i := 0; i < length; i++ { - *out <<= 8 - *out |= int64(n[i]) - } - // Shift up and down in order to sign extend the result. - *out <<= 64 - uint8(length)*8 - *out >>= 64 - uint8(length)*8 - return true -} - -func (s *String) readASN1Uint64(out *uint64) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.INTEGER) || !checkASN1Integer(bytes) || !asn1Unsigned(out, bytes) { - return false - } - return true -} - -func asn1Unsigned(out *uint64, n []byte) bool { - length := len(n) - if length > 9 || length == 9 && n[0] != 0 { - // Too large for uint64. - return false - } - if n[0]&0x80 != 0 { - // Negative number. - return false - } - for i := 0; i < length; i++ { - *out <<= 8 - *out |= uint64(n[i]) - } - return true -} - -// ReadASN1Enum decodes an ASN.1 ENUMERATION into out and advances. It returns -// true on success and false on error. -func (s *String) ReadASN1Enum(out *int) bool { - var bytes String - var i int64 - if !s.ReadASN1(&bytes, asn1.ENUM) || !checkASN1Integer(bytes) || !asn1Signed(&i, bytes) { - return false - } - if int64(int(i)) != i { - return false - } - *out = int(i) - return true -} - -func (s *String) readBase128Int(out *int) bool { - ret := 0 - for i := 0; len(*s) > 0; i++ { - if i == 4 { - return false - } - ret <<= 7 - b := s.read(1)[0] - ret |= int(b & 0x7f) - if b&0x80 == 0 { - *out = ret - return true - } - } - return false // truncated -} - -// ReadASN1ObjectIdentifier decodes an ASN.1 OBJECT IDENTIFIER into out and -// advances. It returns true on success and false on error. -func (s *String) ReadASN1ObjectIdentifier(out *encoding_asn1.ObjectIdentifier) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.OBJECT_IDENTIFIER) || len(bytes) == 0 { - return false - } - - // In the worst case, we get two elements from the first byte (which is - // encoded differently) and then every varint is a single byte long. - components := make([]int, len(bytes)+1) - - // The first varint is 40*value1 + value2: - // According to this packing, value1 can take the values 0, 1 and 2 only. - // When value1 = 0 or value1 = 1, then value2 is <= 39. When value1 = 2, - // then there are no restrictions on value2. - var v int - if !bytes.readBase128Int(&v) { - return false - } - if v < 80 { - components[0] = v / 40 - components[1] = v % 40 - } else { - components[0] = 2 - components[1] = v - 80 - } - - i := 2 - for ; len(bytes) > 0; i++ { - if !bytes.readBase128Int(&v) { - return false - } - components[i] = v - } - *out = components[:i] - return true -} - -// ReadASN1GeneralizedTime decodes an ASN.1 GENERALIZEDTIME into out and -// advances. It returns true on success and false on error. -func (s *String) ReadASN1GeneralizedTime(out *time.Time) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.GeneralizedTime) { - return false - } - t := string(bytes) - res, err := time.Parse(generalizedTimeFormatStr, t) - if err != nil { - return false - } - if serialized := res.Format(generalizedTimeFormatStr); serialized != t { - return false - } - *out = res - return true -} - -// ReadASN1BitString decodes an ASN.1 BIT STRING into out and advances. It -// returns true on success and false on error. -func (s *String) ReadASN1BitString(out *encoding_asn1.BitString) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.BIT_STRING) || len(bytes) == 0 { - return false - } - - paddingBits := uint8(bytes[0]) - bytes = bytes[1:] - if paddingBits > 7 || - len(bytes) == 0 && paddingBits != 0 || - len(bytes) > 0 && bytes[len(bytes)-1]&(1<<paddingBits-1) != 0 { - return false - } - - out.BitLength = len(bytes)*8 - int(paddingBits) - out.Bytes = bytes - return true -} - -// ReadASN1BitString decodes an ASN.1 BIT STRING into out and advances. It is -// an error if the BIT STRING is not a whole number of bytes. This function -// returns true on success and false on error. -func (s *String) ReadASN1BitStringAsBytes(out *[]byte) bool { - var bytes String - if !s.ReadASN1(&bytes, asn1.BIT_STRING) || len(bytes) == 0 { - return false - } - - paddingBits := uint8(bytes[0]) - if paddingBits != 0 { - return false - } - *out = bytes[1:] - return true -} - -// ReadASN1Bytes reads the contents of a DER-encoded ASN.1 element (not including -// tag and length bytes) into out, and advances. The element must match the -// given tag. It returns true on success and false on error. -func (s *String) ReadASN1Bytes(out *[]byte, tag asn1.Tag) bool { - return s.ReadASN1((*String)(out), tag) -} - -// ReadASN1 reads the contents of a DER-encoded ASN.1 element (not including -// tag and length bytes) into out, and advances. The element must match the -// given tag. It returns true on success and false on error. -// -// Tags greater than 30 are not supported (i.e. low-tag-number format only). -func (s *String) ReadASN1(out *String, tag asn1.Tag) bool { - var t asn1.Tag - if !s.ReadAnyASN1(out, &t) || t != tag { - return false - } - return true -} - -// ReadASN1Element reads the contents of a DER-encoded ASN.1 element (including -// tag and length bytes) into out, and advances. The element must match the -// given tag. It returns true on success and false on error. -// -// Tags greater than 30 are not supported (i.e. low-tag-number format only). -func (s *String) ReadASN1Element(out *String, tag asn1.Tag) bool { - var t asn1.Tag - if !s.ReadAnyASN1Element(out, &t) || t != tag { - return false - } - return true -} - -// ReadAnyASN1 reads the contents of a DER-encoded ASN.1 element (not including -// tag and length bytes) into out, sets outTag to its tag, and advances. It -// returns true on success and false on error. -// -// Tags greater than 30 are not supported (i.e. low-tag-number format only). -func (s *String) ReadAnyASN1(out *String, outTag *asn1.Tag) bool { - return s.readASN1(out, outTag, true /* skip header */) -} - -// ReadAnyASN1Element reads the contents of a DER-encoded ASN.1 element -// (including tag and length bytes) into out, sets outTag to is tag, and -// advances. It returns true on success and false on error. -// -// Tags greater than 30 are not supported (i.e. low-tag-number format only). -func (s *String) ReadAnyASN1Element(out *String, outTag *asn1.Tag) bool { - return s.readASN1(out, outTag, false /* include header */) -} - -// PeekASN1Tag returns true if the next ASN.1 value on the string starts with -// the given tag. -func (s String) PeekASN1Tag(tag asn1.Tag) bool { - if len(s) == 0 { - return false - } - return asn1.Tag(s[0]) == tag -} - -// SkipASN1 reads and discards an ASN.1 element with the given tag. -func (s *String) SkipASN1(tag asn1.Tag) bool { - var unused String - return s.ReadASN1(&unused, tag) -} - -// ReadOptionalASN1 attempts to read the contents of a DER-encoded ASN.1 -// element (not including tag and length bytes) tagged with the given tag into -// out. It stores whether an element with the tag was found in outPresent, -// unless outPresent is nil. It returns true on success and false on error. -func (s *String) ReadOptionalASN1(out *String, outPresent *bool, tag asn1.Tag) bool { - present := s.PeekASN1Tag(tag) - if outPresent != nil { - *outPresent = present - } - if present && !s.ReadASN1(out, tag) { - return false - } - return true -} - -// SkipOptionalASN1 advances s over an ASN.1 element with the given tag, or -// else leaves s unchanged. -func (s *String) SkipOptionalASN1(tag asn1.Tag) bool { - if !s.PeekASN1Tag(tag) { - return true - } - var unused String - return s.ReadASN1(&unused, tag) -} - -// ReadOptionalASN1Integer attempts to read an optional ASN.1 INTEGER -// explicitly tagged with tag into out and advances. If no element with a -// matching tag is present, it writes defaultValue into out instead. If out -// does not point to an integer or to a big.Int, it panics. It returns true on -// success and false on error. -func (s *String) ReadOptionalASN1Integer(out interface{}, tag asn1.Tag, defaultValue interface{}) bool { - if reflect.TypeOf(out).Kind() != reflect.Ptr { - panic("out is not a pointer") - } - var present bool - var i String - if !s.ReadOptionalASN1(&i, &present, tag) { - return false - } - if !present { - switch reflect.ValueOf(out).Elem().Kind() { - case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, - reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64: - reflect.ValueOf(out).Elem().Set(reflect.ValueOf(defaultValue)) - case reflect.Struct: - if reflect.TypeOf(out).Elem() != bigIntType { - panic("invalid integer type") - } - if reflect.TypeOf(defaultValue).Kind() != reflect.Ptr || - reflect.TypeOf(defaultValue).Elem() != bigIntType { - panic("out points to big.Int, but defaultValue does not") - } - out.(*big.Int).Set(defaultValue.(*big.Int)) - default: - panic("invalid integer type") - } - return true - } - if !i.ReadASN1Integer(out) || !i.Empty() { - return false - } - return true -} - -// ReadOptionalASN1OctetString attempts to read an optional ASN.1 OCTET STRING -// explicitly tagged with tag into out and advances. If no element with a -// matching tag is present, it writes defaultValue into out instead. It returns -// true on success and false on error. -func (s *String) ReadOptionalASN1OctetString(out *[]byte, outPresent *bool, tag asn1.Tag) bool { - var present bool - var child String - if !s.ReadOptionalASN1(&child, &present, tag) { - return false - } - if outPresent != nil { - *outPresent = present - } - if present { - var oct String - if !child.ReadASN1(&oct, asn1.OCTET_STRING) || !child.Empty() { - return false - } - *out = oct - } else { - *out = nil - } - return true -} - -// ReadOptionalASN1Boolean sets *out to the value of the next ASN.1 BOOLEAN or, -// if the next bytes are not an ASN.1 BOOLEAN, to the value of defaultValue. -func (s *String) ReadOptionalASN1Boolean(out *bool, defaultValue bool) bool { - var present bool - var child String - if !s.ReadOptionalASN1(&child, &present, asn1.BOOLEAN) { - return false - } - - if !present { - *out = defaultValue - return true - } - - return s.ReadASN1Boolean(out) -} - -func (s *String) readASN1(out *String, outTag *asn1.Tag, skipHeader bool) bool { - if len(*s) < 2 { - return false - } - tag, lenByte := (*s)[0], (*s)[1] - - if tag&0x1f == 0x1f { - // ITU-T X.690 section 8.1.2 - // - // An identifier octet with a tag part of 0x1f indicates a high-tag-number - // form identifier with two or more octets. We only support tags less than - // 31 (i.e. low-tag-number form, single octet identifier). - return false - } - - if outTag != nil { - *outTag = asn1.Tag(tag) - } - - // ITU-T X.690 section 8.1.3 - // - // Bit 8 of the first length byte indicates whether the length is short- or - // long-form. - var length, headerLen uint32 // length includes headerLen - if lenByte&0x80 == 0 { - // Short-form length (section 8.1.3.4), encoded in bits 1-7. - length = uint32(lenByte) + 2 - headerLen = 2 - } else { - // Long-form length (section 8.1.3.5). Bits 1-7 encode the number of octets - // used to encode the length. - lenLen := lenByte & 0x7f - var len32 uint32 - - if lenLen == 0 || lenLen > 4 || len(*s) < int(2+lenLen) { - return false - } - - lenBytes := String((*s)[2 : 2+lenLen]) - if !lenBytes.readUnsigned(&len32, int(lenLen)) { - return false - } - - // ITU-T X.690 section 10.1 (DER length forms) requires encoding the length - // with the minimum number of octets. - if len32 < 128 { - // Length should have used short-form encoding. - return false - } - if len32>>((lenLen-1)*8) == 0 { - // Leading octet is 0. Length should have been at least one byte shorter. - return false - } - - headerLen = 2 + uint32(lenLen) - if headerLen+len32 < len32 { - // Overflow. - return false - } - length = headerLen + len32 - } - - if uint32(int(length)) != length || !s.ReadBytes((*[]byte)(out), int(length)) { - return false - } - if skipHeader && !out.Skip(int(headerLen)) { - panic("cryptobyte: internal error") - } - - return true -} |