mirror of
https://github.com/wader/fq.git
synced 2024-12-23 13:22:58 +03:00
9b81d4d3ab
Preparation to make decoder use less memory and API more type safe. Now each scalar type has it's own struct type so it can store different things and enables to have a scalar interface. Also own types will enable experimenting with decode DLS designs like using chained methods that are type aware.
420 lines
12 KiB
Go
420 lines
12 KiB
Go
package asn1
|
|
|
|
// T-REC-X.690-200811 (BER, DER, CER)
|
|
// https://www.itu.int/ITU-T/studygroups/com10/languages/X.690_1297.pdf
|
|
// https://cdn.standards.iteh.ai/samples/12285/039296509e8b40f3b25ba025de60365d/ISO-6093-1985.pdf
|
|
// https://en.wikipedia.org/wiki/X.690
|
|
// https://letsencrypt.org/docs/a-warm-welcome-to-asn1-and-der/
|
|
// https://luca.ntop.org/Teaching/Appunti/asn1.html
|
|
// https://lapo.it/asn1js/
|
|
|
|
// TODO: schema
|
|
// TODO: der/cer via mode?
|
|
// TODO: better torepr
|
|
// TODO: utc time
|
|
// TODO: validate CER DER
|
|
// TODO: bigrat?
|
|
|
|
import (
|
|
"embed"
|
|
"math"
|
|
"strconv"
|
|
"strings"
|
|
|
|
"github.com/wader/fq/format"
|
|
"github.com/wader/fq/pkg/bitio"
|
|
"github.com/wader/fq/pkg/decode"
|
|
"github.com/wader/fq/pkg/interp"
|
|
"github.com/wader/fq/pkg/scalar"
|
|
)
|
|
|
|
//go:embed asn1_ber.jq
|
|
//go:embed asn1_ber.md
|
|
var asn1FS embed.FS
|
|
|
|
func init() {
|
|
interp.RegisterFormat(decode.Format{
|
|
Name: format.ASN1_BER,
|
|
Description: "ASN1 BER (basic encoding rules, also CER and DER)",
|
|
DecodeFn: decodeASN1BER,
|
|
Functions: []string{"torepr"},
|
|
})
|
|
interp.RegisterFS(asn1FS)
|
|
}
|
|
|
|
const (
|
|
classUniversal = 0b00
|
|
classApplication = 0b01
|
|
classContext = 0b10
|
|
classPrivate = 0b11
|
|
)
|
|
|
|
var tagClassMap = scalar.UintMapSymStr{
|
|
classUniversal: "universal",
|
|
classApplication: "application",
|
|
classContext: "context",
|
|
classPrivate: "private",
|
|
}
|
|
|
|
const (
|
|
formPrimitive = 0
|
|
formConstructed = 1
|
|
)
|
|
|
|
var constructedPrimitiveMap = scalar.UintMapSymStr{
|
|
formConstructed: "constructed",
|
|
formPrimitive: "primitive",
|
|
}
|
|
|
|
const (
|
|
universalTypeEndOfContent = 0x00
|
|
universalTypeBoolean = 0x01
|
|
universalTypeInteger = 0x02
|
|
universalTypeBitString = 0x03
|
|
universalTypeOctetString = 0x04
|
|
universalTypeNull = 0x05
|
|
universalTypeObjectIdentifier = 0x06
|
|
universalTypeObjectDescriptor = 0x07 // not encoded, just documentation?
|
|
universalTypeExternal = 0x08
|
|
universalTypeReal = 0x09
|
|
universalTypeEnumerated = 0x0a
|
|
universalTypeEmbedded = 0x0b
|
|
universalTypeUTF8string = 0x0c
|
|
universalTypeSequence = 0x10
|
|
universalTypeSet = 0x11
|
|
universalTypeNumericString = 0x12
|
|
universalTypePrintableString = 0x13
|
|
universalTypeTeletexString = 0x14
|
|
universalTypeVideotexString = 0x15
|
|
universalTypeIA5String = 0x16
|
|
universalTypeUTCTime = 0x17
|
|
universalTypeGeneralizedtime = 0x18
|
|
universalTypeGraphicString = 0x19 // not encoded?
|
|
universalTypeVisibleString = 0x1a
|
|
universalTypeGeneralString = 0x1b
|
|
universalTypeUniversalString = 0x1c // not encoded?
|
|
)
|
|
|
|
var universalTypeMap = scalar.UintMapSymStr{
|
|
universalTypeEndOfContent: "end_of_content",
|
|
universalTypeBoolean: "boolean",
|
|
universalTypeInteger: "integer",
|
|
universalTypeBitString: "bit_string",
|
|
universalTypeOctetString: "octet_string",
|
|
universalTypeNull: "null",
|
|
universalTypeObjectIdentifier: "object_identifier",
|
|
universalTypeObjectDescriptor: "object_descriptor",
|
|
universalTypeExternal: "external",
|
|
universalTypeReal: "real",
|
|
universalTypeEnumerated: "enumerated",
|
|
universalTypeEmbedded: "embedded",
|
|
universalTypeUTF8string: "utf8_string",
|
|
universalTypeSequence: "sequence",
|
|
universalTypeSet: "set",
|
|
universalTypeNumericString: "numeric_string",
|
|
universalTypePrintableString: "printable_string",
|
|
universalTypeTeletexString: "teletex_string",
|
|
universalTypeVideotexString: "videotex_string",
|
|
universalTypeIA5String: "ia5_string",
|
|
universalTypeUTCTime: "utc_time",
|
|
universalTypeGeneralizedtime: "generalized_time",
|
|
universalTypeGraphicString: "graphic_string",
|
|
universalTypeVisibleString: "visible_string",
|
|
universalTypeGeneralString: "general_string",
|
|
universalTypeUniversalString: "universal_string",
|
|
}
|
|
|
|
const (
|
|
lengthIndefinite = 0
|
|
lengthEndMarker = 0x00_00
|
|
)
|
|
|
|
const (
|
|
decimalPlusInfinity = 0b00_00_00
|
|
decimalMinusInfinity = 0b00_00_01
|
|
decimalNan = 0b00_00_10
|
|
decimalMinusZero = 0b00_00_11
|
|
)
|
|
|
|
var lengthMap = scalar.UintMapSymStr{
|
|
0: "indefinite",
|
|
}
|
|
|
|
func decodeLength(d *decode.D) uint64 {
|
|
n := d.U8()
|
|
if n&0b1000_0000 != 0 {
|
|
n = n & 0b0111_1111
|
|
if n == 0 {
|
|
return lengthIndefinite
|
|
}
|
|
if n == 127 {
|
|
d.Errorf("length 127 reserved")
|
|
}
|
|
// TODO: bigint
|
|
return d.U(int(n) * 8)
|
|
}
|
|
return n & 0b0111_1111
|
|
}
|
|
|
|
// TODO: bigint?
|
|
func decodeTagNumber(d *decode.D) uint64 {
|
|
v := d.U5()
|
|
moreBytes := v == 0b11111
|
|
for moreBytes {
|
|
moreBytes = d.Bool()
|
|
v = v<<7 | d.U7()
|
|
}
|
|
return v
|
|
}
|
|
|
|
func decodeASN1BERValue(d *decode.D, bib *bitio.Buffer, sb *strings.Builder, parentForm uint64, parentTag uint64) {
|
|
class := d.FieldU2("class", tagClassMap)
|
|
form := d.FieldU1("form", constructedPrimitiveMap)
|
|
|
|
// TODO: verify
|
|
// TODO: constructed types verify
|
|
_ = parentTag
|
|
_ = parentForm
|
|
|
|
var tag uint64
|
|
switch class {
|
|
case classUniversal:
|
|
tag = d.FieldUintFn("tag", decodeTagNumber, universalTypeMap, scalar.UintHex)
|
|
default:
|
|
tag = d.FieldUintFn("tag", decodeTagNumber)
|
|
}
|
|
|
|
length := d.FieldUintFn("length", decodeLength, lengthMap)
|
|
var l int64
|
|
switch length {
|
|
case lengthIndefinite:
|
|
// null has zero length byte
|
|
if !(class == classUniversal && tag == universalTypeNull) && form == formPrimitive {
|
|
d.Fatalf("primitive with indefinite length")
|
|
}
|
|
l = d.BitsLeft()
|
|
default:
|
|
l = int64(length) * 8
|
|
}
|
|
|
|
d.LimitedFn(l, func(d *decode.D) {
|
|
switch {
|
|
case form == formConstructed || tag == universalTypeSequence || tag == universalTypeSet:
|
|
d.FieldArray("constructed", func(d *decode.D) {
|
|
for !d.End() {
|
|
if length == lengthIndefinite && d.PeekBits(16) == lengthEndMarker {
|
|
break
|
|
}
|
|
|
|
if form == formConstructed && bib == nil && sb == nil {
|
|
switch tag {
|
|
case universalTypeBitString:
|
|
bib = &bitio.Buffer{}
|
|
case universalTypeOctetString:
|
|
bib = &bitio.Buffer{}
|
|
case universalTypeUTF8string,
|
|
universalTypeNumericString,
|
|
universalTypePrintableString,
|
|
universalTypeTeletexString,
|
|
universalTypeVideotexString,
|
|
universalTypeIA5String,
|
|
universalTypeUTCTime,
|
|
universalTypeVisibleString, // not encoded?
|
|
universalTypeGeneralString: // not encoded?
|
|
sb = &strings.Builder{}
|
|
}
|
|
}
|
|
|
|
d.FieldStruct("object", func(d *decode.D) { decodeASN1BERValue(d, bib, sb, form, tag) })
|
|
}
|
|
})
|
|
|
|
if length == lengthIndefinite {
|
|
d.FieldU16("end_marker")
|
|
}
|
|
if form == formConstructed {
|
|
switch tag {
|
|
case universalTypeBitString:
|
|
if bib != nil {
|
|
buf, bufLen := bib.Bits()
|
|
d.FieldRootBitBuf("value", bitio.NewBitReader(buf, bufLen))
|
|
}
|
|
case universalTypeOctetString:
|
|
if bib != nil {
|
|
buf, bufLen := bib.Bits()
|
|
d.FieldRootBitBuf("value", bitio.NewBitReader(buf, bufLen))
|
|
}
|
|
case universalTypeUTF8string,
|
|
universalTypeNumericString,
|
|
universalTypePrintableString,
|
|
universalTypeTeletexString,
|
|
universalTypeVideotexString,
|
|
universalTypeIA5String,
|
|
universalTypeUTCTime,
|
|
universalTypeVisibleString, // not encoded?
|
|
universalTypeGeneralString: // not encoded?
|
|
if sb != nil {
|
|
d.FieldValueStr("value", sb.String())
|
|
}
|
|
}
|
|
}
|
|
case class == classUniversal && tag == universalTypeEndOfContent:
|
|
// nop
|
|
case class == classUniversal && tag == universalTypeBoolean:
|
|
d.FieldU8("value", scalar.UintRangeToScalar{
|
|
{Range: [2]uint64{0, 0}, S: scalar.Uint{Sym: false}},
|
|
{Range: [2]uint64{0x01, 0xff1}, S: scalar.Uint{Sym: true}},
|
|
})
|
|
case class == classUniversal && tag == universalTypeInteger:
|
|
if length > 8 {
|
|
d.FieldSBigInt("value", int(length)*8)
|
|
} else {
|
|
d.FieldS("value", int(length)*8)
|
|
}
|
|
case class == classUniversal && tag == universalTypeBitString:
|
|
unusedBitsCount := d.FieldU8("unused_bits_count")
|
|
if unusedBitsCount > 7 {
|
|
d.Fatalf("unusedBitsCount %d > 7", unusedBitsCount)
|
|
}
|
|
br := d.FieldRawLen("value", int64(length-1)*8-int64(unusedBitsCount))
|
|
if bib != nil {
|
|
// TODO: helper?
|
|
if _, err := bitio.Copy(bib, br); err != nil {
|
|
d.IOPanic(err, "bitio.Copy")
|
|
}
|
|
}
|
|
if unusedBitsCount > 0 {
|
|
d.FieldRawLen("unused_bits", int64(unusedBitsCount))
|
|
}
|
|
case class == classUniversal && tag == universalTypeOctetString:
|
|
br := d.FieldRawLen("value", int64(length)*8)
|
|
if bib != nil {
|
|
// TODO: helper?
|
|
if _, err := bitio.Copy(bib, br); err != nil {
|
|
d.IOPanic(err, "bitio.Copy")
|
|
}
|
|
}
|
|
case class == classUniversal && tag == universalTypeNull:
|
|
d.FieldValueAny("value", nil)
|
|
case class == classUniversal && tag == universalTypeObjectIdentifier:
|
|
d.FieldArray("value", func(d *decode.D) {
|
|
// first byte is = oid0*40 + oid1
|
|
d.FieldUintFn("oid", func(d *decode.D) uint64 { return d.U8() / 40 })
|
|
d.SeekRel(-8)
|
|
d.FieldUintFn("oid", func(d *decode.D) uint64 { return d.U8() % 40 })
|
|
for !d.End() {
|
|
d.FieldUintFn("oid", func(d *decode.D) uint64 {
|
|
more := true
|
|
var n uint64
|
|
for more {
|
|
b := d.U8()
|
|
n = n<<7 | b&0b0111_1111
|
|
more = b&0b1000_0000 != 0
|
|
}
|
|
return n
|
|
})
|
|
}
|
|
})
|
|
case class == classUniversal && tag == universalTypeObjectDescriptor: // not encoded, just documentation?
|
|
// nop
|
|
case class == classUniversal && tag == universalTypeExternal:
|
|
d.FieldRawLen("value", int64(length)*8)
|
|
case class == classUniversal && tag == universalTypeReal:
|
|
switch {
|
|
case length == 0:
|
|
d.FieldValueUint("value", 0)
|
|
default:
|
|
switch d.FieldBool("binary_encoding") {
|
|
case true:
|
|
s := d.FieldScalarBool("sign", scalar.BoolMapSymSint{
|
|
true: -1,
|
|
false: 1,
|
|
}).SymSint()
|
|
base := d.FieldScalarU2("base", scalar.UintMapSymUint{
|
|
0b00: 2,
|
|
0b01: 8,
|
|
0b10: 16,
|
|
0b11: 0,
|
|
}).SymUint()
|
|
scale := d.FieldU2("scale")
|
|
format := d.FieldU2("format")
|
|
|
|
var exp int64
|
|
switch format {
|
|
case 0b00:
|
|
exp = d.FieldS8("exp")
|
|
case 0b01:
|
|
exp = d.FieldS16("exp")
|
|
case 0b10:
|
|
exp = d.FieldS24("exp")
|
|
default:
|
|
n := d.FieldU8("exp_bytes")
|
|
// TODO: bigint?
|
|
exp = d.FieldS("exp", int(n)*8)
|
|
}
|
|
|
|
n := d.FieldU("n", int(d.BitsLeft()))
|
|
m := float64(s) * float64(n) * math.Pow(float64(base), float64(exp)) * float64(int(1)<<scale)
|
|
d.FieldValueFlt("value", m)
|
|
|
|
case false:
|
|
switch d.FieldBool("decimal_encoding") {
|
|
case true:
|
|
n := d.FieldU6("special", scalar.UintMapSymStr{
|
|
decimalPlusInfinity: "plus_infinity",
|
|
decimalMinusInfinity: "minus_infinity",
|
|
decimalNan: "nan",
|
|
decimalMinusZero: "minus_zero",
|
|
})
|
|
|
|
switch n {
|
|
case decimalPlusInfinity:
|
|
d.FieldValueFlt("value", math.Inf(1))
|
|
case decimalMinusInfinity:
|
|
d.FieldValueFlt("value", math.Inf(-1))
|
|
case decimalNan:
|
|
d.FieldValueFlt("value", math.NaN())
|
|
case decimalMinusZero:
|
|
d.FieldValueFlt("value", -0)
|
|
}
|
|
case false:
|
|
d.FieldU6("representation", scalar.UintMapSymStr{
|
|
0b00_00_01: "nr1",
|
|
0b00_00_10: "nr2",
|
|
0b00_00_11: "nr3",
|
|
})
|
|
d.FieldFltFn("value", func(d *decode.D) float64 {
|
|
// TODO: can ParseFloat do all ISO-6093 nr?
|
|
n, _ := strconv.ParseFloat(d.UTF8(int(d.BitsLeft()/8)), 64)
|
|
return n
|
|
})
|
|
}
|
|
}
|
|
}
|
|
case class == classUniversal && tag == universalTypeUTF8string,
|
|
class == classUniversal && tag == universalTypeNumericString,
|
|
class == classUniversal && tag == universalTypePrintableString,
|
|
class == classUniversal && tag == universalTypeTeletexString,
|
|
class == classUniversal && tag == universalTypeVideotexString,
|
|
class == classUniversal && tag == universalTypeIA5String,
|
|
class == classUniversal && tag == universalTypeUTCTime,
|
|
class == classUniversal && tag == universalTypeVisibleString, // not encoded?
|
|
class == classUniversal && tag == universalTypeGeneralString: // not encoded?
|
|
// TODO: restrict?
|
|
s := d.FieldUTF8("value", int(length))
|
|
if sb != nil {
|
|
sb.WriteString(s)
|
|
}
|
|
case class == classUniversal && tag == universalTypeGeneralizedtime:
|
|
d.FieldRawLen("value", int64(length)*8)
|
|
default:
|
|
d.FieldRawLen("value", l)
|
|
}
|
|
})
|
|
}
|
|
|
|
func decodeASN1BER(d *decode.D, _ any) any {
|
|
decodeASN1BERValue(d, nil, nil, formConstructed, universalTypeSequence)
|
|
return nil
|
|
}
|