Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 | 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 1x 4x 4x 4x 4x 64x 64x 64x 64x 64x 64x 64x 64x 64x 64x 64x 47x 47x 17x 17x 31x 31x 17x 17x 37x 37x 37x 37x 37x 37x 60x 60x 33x 33x 33x 27x 37x 27x 27x 27x 5x 5x 22x 12x 12x 10x 1x 1x 9x 3x 3x 6x 2x 2x 2x 4x 1x 1x 3x 3x 3x | import {CursorDataView} from '../../../CursorDataView';
import {ASN1Message} from '../../../interfaces/ASN1Message';
import {BERLength} from '../../../interfaces/BERLength';
import {LengthType} from '../../../interfaces/LengthType';
import {TagUniversal} from '../../../interfaces/TagUniversal';
import {TagDecoder} from '../../../TagDecoder';
import {Identifier} from './Identifier';
import {getTagClass, isConstructed} from './misc';
import {readBitString} from './primitive/ReadBitString';
import {readBoolean} from './primitive/ReadBoolean';
import {readIA5String} from './primitive/ReadIA5String';
import {readInteger} from './primitive/ReadInteger';
import {readObjectIdentifier} from './primitive/ReadObjectIdentifier';
import {readOctetString} from './primitive/ReadOctetString';
export function BERDecode(input: ArrayBuffer): ASN1Message {
const cdv = new CursorDataView(input);
const identifier = readIdentifierOctets(cdv);
Eif (identifier.isComposed()) {
return readComposed(cdv, identifier);
}
return readSimple(cdv, identifier);
}
function readIdentifierOctets(cdv: CursorDataView): Identifier {
const result = new Identifier();
const octet = cdv.read();
// (8.1.2.2 a)
result.tagClass = getTagClass(octet);
// (8.1.2.2 b)
result.constructed = isConstructed(octet);
// (8.1.2.4.1 c)
result.tag = octet & 0b0001_1111;
Eif (result.tag < 0b0001_1111) {
return result;
}
// multi octets.
let tagNumberStr = '';
let octetN;
while (true) {
octetN = cdv.read();
// bit 7 to 1 (8.1.2.4.2 b)
const str = (octetN & 0b0111_1111).toString(2);
console.log('str: ', str);
tagNumberStr += str;
// last octet (8.1.2.4.2 a)
if ((octetN & 0b1000_0000) === 0) {
break;
}
}
// (8.1.2.4.2 b) concactenation
result.tag = parseInt(tagNumberStr, 2);
return result;
}
function readLengthOctets(cdv: CursorDataView): BERLength {
const berLength: BERLength = {type: LengthType.DEFINITE, length: 0};
const length = cdv.read();
// (8.1.3.6.1): indefinite form
Iif (length === 0b1000_0000) {
return {type: LengthType.INDEFINITE, length: -1};
}
// (8.1.3.4): one octet case (<=127, definite form)
if ((length & 0b1000_0000) === 0) {
berLength.length = length;
return berLength;
}
// (8.1.3.5 b) Big Length case (>127)
let bigLength = 0;
for (let i = 0; i < length - 0b1000_0000; i++) {
const nbr = cdv.read();
bigLength = bigLength * 256 + nbr;
}
berLength.length = bigLength;
return berLength;
}
function readComposed(
cdv: CursorDataView,
identifier: Identifier
): ASN1Message {
const {length, type} = readLengthOctets(cdv);
const result: ASN1Message = {
tagClass: identifier.tagClass,
isConstructed: identifier.constructed,
tagCode: identifier.tag,
tagLabel: TagDecoder.getLabel(identifier.tagClass, identifier.tag),
length: length,
lengthType: type,
value: null,
};
Iif (length === 0) {
return result;
}
const max = cdv.index + length;
result.value = [];
while (cdv.index < max) {
const ident = readIdentifierOctets(cdv);
if (ident.isComposed()) {
const a = readComposed(cdv, ident);
result.value.push(a);
continue;
}
result.value.push(readSimple(cdv, ident));
}
return result;
}
function readSimple(cdv: CursorDataView, identifier: Identifier): ASN1Message {
const {length, type} = readLengthOctets(cdv);
const result: ASN1Message = {
tagClass: identifier.tagClass,
isConstructed: identifier.constructed,
tagCode: identifier.tag,
tagLabel: TagDecoder.getLabel(identifier.tagClass, identifier.tag),
length: length,
lengthType: type,
value: null,
};
if (identifier.tag === TagUniversal.BOOLEAN.code) {
result.value = readBoolean(cdv, length);
return result;
}
if (identifier.tag === TagUniversal.INTEGER.code) {
result.value = readInteger(cdv, length);
return result;
}
if (identifier.tag === TagUniversal.BIT_STRING.code) {
// 8.6.1 The encoding of a bitstring value shall be either primitive
// or constructed at the option of the sender.
result.value = readBitString(cdv, length);
return result;
}
if (identifier.tag === TagUniversal.OCTET_STRING.code) {
// 8.7.1 The encoding of an octetstring value shall be either primitive
// or constructed at the option of the sender.
result.value = readOctetString(cdv, length);
return result;
}
if (identifier.tag === TagUniversal.OBJECT_IDENTIFIER.code) {
Iif (identifier.constructed) {
throw new Error(
'The encoding of an Object Identifier should be primitive (clause 8.19.1).'
);
}
result.value = readObjectIdentifier(cdv, length);
return result;
}
if (identifier.tag === TagUniversal.IA5STRING.code) {
result.value = readIA5String(cdv, length);
return result;
}
Eif (identifier.tag === TagUniversal.GENERAL_STRING.code) {
result.value = readIA5String(cdv, length);
return result;
}
throw new Error(
`cannot understand the identifier tag number: ${identifier.tag}`
);
}
|