diff options
Diffstat (limited to 'src/vendor/golang.org/x/crypto/cryptobyte')
| -rw-r--r-- | src/vendor/golang.org/x/crypto/cryptobyte/asn1.go | 816 | ||||
| -rw-r--r-- | src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go | 46 | ||||
| -rw-r--r-- | src/vendor/golang.org/x/crypto/cryptobyte/builder.go | 342 | ||||
| -rw-r--r-- | src/vendor/golang.org/x/crypto/cryptobyte/string.go | 172 |
4 files changed, 1376 insertions, 0 deletions
diff --git a/src/vendor/golang.org/x/crypto/cryptobyte/asn1.go b/src/vendor/golang.org/x/crypto/cryptobyte/asn1.go new file mode 100644 index 0000000..401414d --- /dev/null +++ b/src/vendor/golang.org/x/crypto/cryptobyte/asn1.go @@ -0,0 +1,816 @@ +// 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) +} + +// AddASN1Int64WithTag appends a DER-encoded ASN.1 INTEGER with the +// given tag. +func (b *Builder) AddASN1Int64WithTag(v int64, tag asn1.Tag) { + b.addASN1Signed(tag, 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 len(bytes) == 0 || 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))) + }) +} + +// AddASN1UTCTime appends a DER-encoded ASN.1 UTCTime. +func (b *Builder) AddASN1UTCTime(t time.Time) { + b.AddASN1(asn1.UTCTime, func(c *Builder) { + // As utilized by the X.509 profile, UTCTime can only + // represent the years 1950 through 2049. + if t.Year() < 1950 || t.Year() >= 2050 { + b.err = fmt.Errorf("cryptobyte: cannot represent %v as a UTCTime", t) + return + } + c.AddBytes([]byte(t.Format(defaultUTCTimeFormatStr))) + }) +} + +// 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 + +// ReadASN1Boolean decodes an ASN.1 BOOLEAN and converts it to a boolean +// representation into out and advances. It reports whether the read +// was successful. +func (s *String) ReadASN1Boolean(out *bool) bool { + var bytes String + if !s.ReadASN1(&bytes, asn1.BOOLEAN) || len(bytes) != 1 { + return false + } + + switch bytes[0] { + case 0: + *out = false + case 0xff: + *out = true + default: + return false + } + + return true +} + +// ReadASN1Integer decodes an ASN.1 INTEGER into out and advances. If out does +// not point to an integer, to a big.Int, or to a []byte it panics. Only +// positive and zero values can be decoded into []byte, and they are returned as +// big-endian binary values that share memory with s. Positive values will have +// no leading zeroes, and zero will be returned as a single zero byte. +// ReadASN1Integer reports whether the read was successful. +func (s *String) ReadASN1Integer(out interface{}) bool { + switch out := out.(type) { + case *int, *int8, *int16, *int32, *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 *uint, *uint8, *uint16, *uint32, *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 *big.Int: + return s.readASN1BigInt(out) + case *[]byte: + return s.readASN1Bytes(out) + default: + 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) readASN1Bytes(out *[]byte) bool { + var bytes String + if !s.ReadASN1(&bytes, asn1.INTEGER) || !checkASN1Integer(bytes) { + return false + } + if bytes[0]&0x80 == 0x80 { + return false + } + for len(bytes) > 1 && bytes[0] == 0 { + bytes = bytes[1:] + } + *out = 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 +} + +// ReadASN1Int64WithTag decodes an ASN.1 INTEGER with the given tag into out +// and advances. It reports whether the read was successful and resulted in a +// value that can be represented in an int64. +func (s *String) ReadASN1Int64WithTag(out *int64, tag asn1.Tag) bool { + var bytes String + return s.ReadASN1(&bytes, tag) && checkASN1Integer(bytes) && asn1Signed(out, bytes) +} + +// ReadASN1Enum decodes an ASN.1 ENUMERATION into out and advances. It reports +// whether the read was successful. +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 == 5 { + return false + } + // Avoid overflowing int on a 32-bit platform. + // We don't want different behavior based on the architecture. + if ret >= 1<<(31-7) { + 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 reports whether the read was successful. +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 reports whether the read was successful. +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 +} + +const defaultUTCTimeFormatStr = "060102150405Z0700" + +// ReadASN1UTCTime decodes an ASN.1 UTCTime into out and advances. +// It reports whether the read was successful. +func (s *String) ReadASN1UTCTime(out *time.Time) bool { + var bytes String + if !s.ReadASN1(&bytes, asn1.UTCTime) { + return false + } + t := string(bytes) + + formatStr := defaultUTCTimeFormatStr + var err error + res, err := time.Parse(formatStr, t) + if err != nil { + // Fallback to minute precision if we can't parse second + // precision. If we are following X.509 or X.690 we shouldn't + // support this, but we do. + formatStr = "0601021504Z0700" + res, err = time.Parse(formatStr, t) + } + if err != nil { + return false + } + + if serialized := res.Format(formatStr); serialized != t { + return false + } + + if res.Year() >= 2050 { + // UTCTime interprets the low order digits 50-99 as 1950-99. + // This only applies to its use in the X.509 profile. + // See https://tools.ietf.org/html/rfc5280#section-4.1.2.5.1 + res = res.AddDate(-100, 0, 0) + } + *out = res + return true +} + +// ReadASN1BitString decodes an ASN.1 BIT STRING into out and advances. +// It reports whether the read was successful. +func (s *String) ReadASN1BitString(out *encoding_asn1.BitString) bool { + var bytes String + if !s.ReadASN1(&bytes, asn1.BIT_STRING) || len(bytes) == 0 || + len(bytes)*8/8 != len(bytes) { + return false + } + + paddingBits := 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. It reports +// whether the read was successful. +func (s *String) ReadASN1BitStringAsBytes(out *[]byte) bool { + var bytes String + if !s.ReadASN1(&bytes, asn1.BIT_STRING) || len(bytes) == 0 { + return false + } + + paddingBits := 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 reports whether the read was successful. +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 reports whether the read was successful. +// +// 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 reports whether the read was successful. +// +// 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 reports whether the read was successful. +// +// 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 reports whether the read was successful. +// +// 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 reports whether 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. It +// reports whether the operation was successful. +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 reports whether the read was successful. +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. It reports whether the operation was successful. +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. Otherwise, it behaves like +// ReadASN1Integer. +func (s *String) ReadOptionalASN1Integer(out interface{}, tag asn1.Tag, defaultValue interface{}) bool { + var present bool + var i String + if !s.ReadOptionalASN1(&i, &present, tag) { + return false + } + if !present { + switch out.(type) { + case *int, *int8, *int16, *int32, *int64, + *uint, *uint8, *uint16, *uint32, *uint64, *[]byte: + reflect.ValueOf(out).Elem().Set(reflect.ValueOf(defaultValue)) + case *big.Int: + if defaultValue, ok := defaultValue.(*big.Int); ok { + out.(*big.Int).Set(defaultValue) + } else { + panic("out points to big.Int, but defaultValue does not") + } + 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 sets "out" to nil instead. It reports +// whether the read was successful. +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. +// It reports whether the operation was successful. +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 int(length) < 0 || !s.ReadBytes((*[]byte)(out), int(length)) { + return false + } + if skipHeader && !out.Skip(int(headerLen)) { + panic("cryptobyte: internal error") + } + + return true +} diff --git a/src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go b/src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go new file mode 100644 index 0000000..cda8e3e --- /dev/null +++ b/src/vendor/golang.org/x/crypto/cryptobyte/asn1/asn1.go @@ -0,0 +1,46 @@ +// 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 asn1 contains supporting types for parsing and building ASN.1 +// messages with the cryptobyte package. +package asn1 // import "golang.org/x/crypto/cryptobyte/asn1" + +// Tag represents an ASN.1 identifier octet, consisting of a tag number +// (indicating a type) and class (such as context-specific or constructed). +// +// Methods in the cryptobyte package only support the low-tag-number form, i.e. +// a single identifier octet with bits 7-8 encoding the class and bits 1-6 +// encoding the tag number. +type Tag uint8 + +const ( + classConstructed = 0x20 + classContextSpecific = 0x80 +) + +// Constructed returns t with the constructed class bit set. +func (t Tag) Constructed() Tag { return t | classConstructed } + +// ContextSpecific returns t with the context-specific class bit set. +func (t Tag) ContextSpecific() Tag { return t | classContextSpecific } + +// The following is a list of standard tag and class combinations. +const ( + BOOLEAN = Tag(1) + INTEGER = Tag(2) + BIT_STRING = Tag(3) + OCTET_STRING = Tag(4) + NULL = Tag(5) + OBJECT_IDENTIFIER = Tag(6) + ENUM = Tag(10) + UTF8String = Tag(12) + SEQUENCE = Tag(16 | classConstructed) + SET = Tag(17 | classConstructed) + PrintableString = Tag(19) + T61String = Tag(20) + IA5String = Tag(22) + UTCTime = Tag(23) + GeneralizedTime = Tag(24) + GeneralString = Tag(27) +) diff --git a/src/vendor/golang.org/x/crypto/cryptobyte/builder.go b/src/vendor/golang.org/x/crypto/cryptobyte/builder.go new file mode 100644 index 0000000..2a90c59 --- /dev/null +++ b/src/vendor/golang.org/x/crypto/cryptobyte/builder.go @@ -0,0 +1,342 @@ +// 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 ( + "errors" + "fmt" +) + +// A Builder builds byte strings from fixed-length and length-prefixed values. +// Builders either allocate space as needed, or are ‘fixed’, which means that +// they write into a given buffer and produce an error if it's exhausted. +// +// The zero value is a usable Builder that allocates space as needed. +// +// Simple values are marshaled and appended to a Builder using methods on the +// Builder. Length-prefixed values are marshaled by providing a +// BuilderContinuation, which is a function that writes the inner contents of +// the value to a given Builder. See the documentation for BuilderContinuation +// for details. +type Builder struct { + err error + result []byte + fixedSize bool + child *Builder + offset int + pendingLenLen int + pendingIsASN1 bool + inContinuation *bool +} + +// NewBuilder creates a Builder that appends its output to the given buffer. +// Like append(), the slice will be reallocated if its capacity is exceeded. +// Use Bytes to get the final buffer. +func NewBuilder(buffer []byte) *Builder { + return &Builder{ + result: buffer, + } +} + +// NewFixedBuilder creates a Builder that appends its output into the given +// buffer. This builder does not reallocate the output buffer. Writes that +// would exceed the buffer's capacity are treated as an error. +func NewFixedBuilder(buffer []byte) *Builder { + return &Builder{ + result: buffer, + fixedSize: true, + } +} + +// SetError sets the value to be returned as the error from Bytes. Writes +// performed after calling SetError are ignored. +func (b *Builder) SetError(err error) { + b.err = err +} + +// Bytes returns the bytes written by the builder or an error if one has +// occurred during building. +func (b *Builder) Bytes() ([]byte, error) { + if b.err != nil { + return nil, b.err + } + return b.result[b.offset:], nil +} + +// BytesOrPanic returns the bytes written by the builder or panics if an error +// has occurred during building. +func (b *Builder) BytesOrPanic() []byte { + if b.err != nil { + panic(b.err) + } + return b.result[b.offset:] +} + +// AddUint8 appends an 8-bit value to the byte string. +func (b *Builder) AddUint8(v uint8) { + b.add(byte(v)) +} + +// AddUint16 appends a big-endian, 16-bit value to the byte string. +func (b *Builder) AddUint16(v uint16) { + b.add(byte(v>>8), byte(v)) +} + +// AddUint24 appends a big-endian, 24-bit value to the byte string. The highest +// byte of the 32-bit input value is silently truncated. +func (b *Builder) AddUint24(v uint32) { + b.add(byte(v>>16), byte(v>>8), byte(v)) +} + +// AddUint32 appends a big-endian, 32-bit value to the byte string. +func (b *Builder) AddUint32(v uint32) { + b.add(byte(v>>24), byte(v>>16), byte(v>>8), byte(v)) +} + +// AddUint64 appends a big-endian, 64-bit value to the byte string. +func (b *Builder) AddUint64(v uint64) { + b.add(byte(v>>56), byte(v>>48), byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8), byte(v)) +} + +// AddBytes appends a sequence of bytes to the byte string. +func (b *Builder) AddBytes(v []byte) { + b.add(v...) +} + +// BuilderContinuation is a continuation-passing interface for building +// length-prefixed byte sequences. Builder methods for length-prefixed +// sequences (AddUint8LengthPrefixed etc) will invoke the BuilderContinuation +// supplied to them. The child builder passed to the continuation can be used +// to build the content of the length-prefixed sequence. For example: +// +// parent := cryptobyte.NewBuilder() +// parent.AddUint8LengthPrefixed(func (child *Builder) { +// child.AddUint8(42) +// child.AddUint8LengthPrefixed(func (grandchild *Builder) { +// grandchild.AddUint8(5) +// }) +// }) +// +// It is an error to write more bytes to the child than allowed by the reserved +// length prefix. After the continuation returns, the child must be considered +// invalid, i.e. users must not store any copies or references of the child +// that outlive the continuation. +// +// If the continuation panics with a value of type BuildError then the inner +// error will be returned as the error from Bytes. If the child panics +// otherwise then Bytes will repanic with the same value. +type BuilderContinuation func(child *Builder) + +// BuildError wraps an error. If a BuilderContinuation panics with this value, +// the panic will be recovered and the inner error will be returned from +// Builder.Bytes. +type BuildError struct { + Err error +} + +// AddUint8LengthPrefixed adds a 8-bit length-prefixed byte sequence. +func (b *Builder) AddUint8LengthPrefixed(f BuilderContinuation) { + b.addLengthPrefixed(1, false, f) +} + +// AddUint16LengthPrefixed adds a big-endian, 16-bit length-prefixed byte sequence. +func (b *Builder) AddUint16LengthPrefixed(f BuilderContinuation) { + b.addLengthPrefixed(2, false, f) +} + +// AddUint24LengthPrefixed adds a big-endian, 24-bit length-prefixed byte sequence. +func (b *Builder) AddUint24LengthPrefixed(f BuilderContinuation) { + b.addLengthPrefixed(3, false, f) +} + +// AddUint32LengthPrefixed adds a big-endian, 32-bit length-prefixed byte sequence. +func (b *Builder) AddUint32LengthPrefixed(f BuilderContinuation) { + b.addLengthPrefixed(4, false, f) +} + +func (b *Builder) callContinuation(f BuilderContinuation, arg *Builder) { + if !*b.inContinuation { + *b.inContinuation = true + + defer func() { + *b.inContinuation = false + + r := recover() + if r == nil { + return + } + + if buildError, ok := r.(BuildError); ok { + b.err = buildError.Err + } else { + panic(r) + } + }() + } + + f(arg) +} + +func (b *Builder) addLengthPrefixed(lenLen int, isASN1 bool, f BuilderContinuation) { + // Subsequent writes can be ignored if the builder has encountered an error. + if b.err != nil { + return + } + + offset := len(b.result) + b.add(make([]byte, lenLen)...) + + if b.inContinuation == nil { + b.inContinuation = new(bool) + } + + b.child = &Builder{ + result: b.result, + fixedSize: b.fixedSize, + offset: offset, + pendingLenLen: lenLen, + pendingIsASN1: isASN1, + inContinuation: b.inContinuation, + } + + b.callContinuation(f, b.child) + b.flushChild() + if b.child != nil { + panic("cryptobyte: internal error") + } +} + +func (b *Builder) flushChild() { + if b.child == nil { + return + } + b.child.flushChild() + child := b.child + b.child = nil + + if child.err != nil { + b.err = child.err + return + } + + length := len(child.result) - child.pendingLenLen - child.offset + + if length < 0 { + panic("cryptobyte: internal error") // result unexpectedly shrunk + } + + if child.pendingIsASN1 { + // For ASN.1, we reserved a single byte for the length. If that turned out + // to be incorrect, we have to move the contents along in order to make + // space. + if child.pendingLenLen != 1 { + panic("cryptobyte: internal error") + } + var lenLen, lenByte uint8 + if int64(length) > 0xfffffffe { + b.err = errors.New("pending ASN.1 child too long") + return + } else if length > 0xffffff { + lenLen = 5 + lenByte = 0x80 | 4 + } else if length > 0xffff { + lenLen = 4 + lenByte = 0x80 | 3 + } else if length > 0xff { + lenLen = 3 + lenByte = 0x80 | 2 + } else if length > 0x7f { + lenLen = 2 + lenByte = 0x80 | 1 + } else { + lenLen = 1 + lenByte = uint8(length) + length = 0 + } + + // Insert the initial length byte, make space for successive length bytes, + // and adjust the offset. + child.result[child.offset] = lenByte + extraBytes := int(lenLen - 1) + if extraBytes != 0 { + child.add(make([]byte, extraBytes)...) + childStart := child.offset + child.pendingLenLen + copy(child.result[childStart+extraBytes:], child.result[childStart:]) + } + child.offset++ + child.pendingLenLen = extraBytes + } + + l := length + for i := child.pendingLenLen - 1; i >= 0; i-- { + child.result[child.offset+i] = uint8(l) + l >>= 8 + } + if l != 0 { + b.err = fmt.Errorf("cryptobyte: pending child length %d exceeds %d-byte length prefix", length, child.pendingLenLen) + return + } + + if b.fixedSize && &b.result[0] != &child.result[0] { + panic("cryptobyte: BuilderContinuation reallocated a fixed-size buffer") + } + + b.result = child.result +} + +func (b *Builder) add(bytes ...byte) { + if b.err != nil { + return + } + if b.child != nil { + panic("cryptobyte: attempted write while child is pending") + } + if len(b.result)+len(bytes) < len(bytes) { + b.err = errors.New("cryptobyte: length overflow") + } + if b.fixedSize && len(b.result)+len(bytes) > cap(b.result) { + b.err = errors.New("cryptobyte: Builder is exceeding its fixed-size buffer") + return + } + b.result = append(b.result, bytes...) +} + +// Unwrite rolls back n bytes written directly to the Builder. An attempt by a +// child builder passed to a continuation to unwrite bytes from its parent will +// panic. +func (b *Builder) Unwrite(n int) { + if b.err != nil { + return + } + if b.child != nil { + panic("cryptobyte: attempted unwrite while child is pending") + } + length := len(b.result) - b.pendingLenLen - b.offset + if length < 0 { + panic("cryptobyte: internal error") + } + if n > length { + panic("cryptobyte: attempted to unwrite more than was written") + } + b.result = b.result[:len(b.result)-n] +} + +// A MarshalingValue marshals itself into a Builder. +type MarshalingValue interface { + // Marshal is called by Builder.AddValue. It receives a pointer to a builder + // to marshal itself into. It may return an error that occurred during + // marshaling, such as unset or invalid values. + Marshal(b *Builder) error +} + +// AddValue calls Marshal on v, passing a pointer to the builder to append to. +// If Marshal returns an error, it is set on the Builder so that subsequent +// appends don't have an effect. +func (b *Builder) AddValue(v MarshalingValue) { + err := v.Marshal(b) + if err != nil { + b.err = err + } +} diff --git a/src/vendor/golang.org/x/crypto/cryptobyte/string.go b/src/vendor/golang.org/x/crypto/cryptobyte/string.go new file mode 100644 index 0000000..0531a3d --- /dev/null +++ b/src/vendor/golang.org/x/crypto/cryptobyte/string.go @@ -0,0 +1,172 @@ +// 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 contains types that help with parsing and constructing +// length-prefixed, binary messages, including ASN.1 DER. (The asn1 subpackage +// contains useful ASN.1 constants.) +// +// The String type is for parsing. It wraps a []byte slice and provides helper +// functions for consuming structures, value by value. +// +// The Builder type is for constructing messages. It providers helper functions +// for appending values and also for appending length-prefixed submessages – +// without having to worry about calculating the length prefix ahead of time. +// +// See the documentation and examples for the Builder and String types to get +// started. +package cryptobyte // import "golang.org/x/crypto/cryptobyte" + +// String represents a string of bytes. It provides methods for parsing +// fixed-length and length-prefixed values from it. +type String []byte + +// read advances a String by n bytes and returns them. If less than n bytes +// remain, it returns nil. +func (s *String) read(n int) []byte { + if len(*s) < n || n < 0 { + return nil + } + v := (*s)[:n] + *s = (*s)[n:] + return v +} + +// Skip advances the String by n byte and reports whether it was successful. +func (s *String) Skip(n int) bool { + return s.read(n) != nil +} + +// ReadUint8 decodes an 8-bit value into out and advances over it. +// It reports whether the read was successful. +func (s *String) ReadUint8(out *uint8) bool { + v := s.read(1) + if v == nil { + return false + } + *out = uint8(v[0]) + return true +} + +// ReadUint16 decodes a big-endian, 16-bit value into out and advances over it. +// It reports whether the read was successful. +func (s *String) ReadUint16(out *uint16) bool { + v := s.read(2) + if v == nil { + return false + } + *out = uint16(v[0])<<8 | uint16(v[1]) + return true +} + +// ReadUint24 decodes a big-endian, 24-bit value into out and advances over it. +// It reports whether the read was successful. +func (s *String) ReadUint24(out *uint32) bool { + v := s.read(3) + if v == nil { + return false + } + *out = uint32(v[0])<<16 | uint32(v[1])<<8 | uint32(v[2]) + return true +} + +// ReadUint32 decodes a big-endian, 32-bit value into out and advances over it. +// It reports whether the read was successful. +func (s *String) ReadUint32(out *uint32) bool { + v := s.read(4) + if v == nil { + return false + } + *out = uint32(v[0])<<24 | uint32(v[1])<<16 | uint32(v[2])<<8 | uint32(v[3]) + return true +} + +// ReadUint64 decodes a big-endian, 64-bit value into out and advances over it. +// It reports whether the read was successful. +func (s *String) ReadUint64(out *uint64) bool { + v := s.read(8) + if v == nil { + return false + } + *out = uint64(v[0])<<56 | uint64(v[1])<<48 | uint64(v[2])<<40 | uint64(v[3])<<32 | uint64(v[4])<<24 | uint64(v[5])<<16 | uint64(v[6])<<8 | uint64(v[7]) + return true +} + +func (s *String) readUnsigned(out *uint32, length int) bool { + v := s.read(length) + if v == nil { + return false + } + var result uint32 + for i := 0; i < length; i++ { + result <<= 8 + result |= uint32(v[i]) + } + *out = result + return true +} + +func (s *String) readLengthPrefixed(lenLen int, outChild *String) bool { + lenBytes := s.read(lenLen) + if lenBytes == nil { + return false + } + var length uint32 + for _, b := range lenBytes { + length = length << 8 + length = length | uint32(b) + } + v := s.read(int(length)) + if v == nil { + return false + } + *outChild = v + return true +} + +// ReadUint8LengthPrefixed reads the content of an 8-bit length-prefixed value +// into out and advances over it. It reports whether the read was successful. +func (s *String) ReadUint8LengthPrefixed(out *String) bool { + return s.readLengthPrefixed(1, out) +} + +// ReadUint16LengthPrefixed reads the content of a big-endian, 16-bit +// length-prefixed value into out and advances over it. It reports whether the +// read was successful. +func (s *String) ReadUint16LengthPrefixed(out *String) bool { + return s.readLengthPrefixed(2, out) +} + +// ReadUint24LengthPrefixed reads the content of a big-endian, 24-bit +// length-prefixed value into out and advances over it. It reports whether +// the read was successful. +func (s *String) ReadUint24LengthPrefixed(out *String) bool { + return s.readLengthPrefixed(3, out) +} + +// ReadBytes reads n bytes into out and advances over them. It reports +// whether the read was successful. +func (s *String) ReadBytes(out *[]byte, n int) bool { + v := s.read(n) + if v == nil { + return false + } + *out = v + return true +} + +// CopyBytes copies len(out) bytes into out and advances over them. It reports +// whether the copy operation was successful +func (s *String) CopyBytes(out []byte) bool { + n := len(out) + v := s.read(n) + if v == nil { + return false + } + return copy(out, v) == n +} + +// Empty reports whether the string does not contain any bytes. +func (s String) Empty() bool { + return len(s) == 0 +} |