27 lines
754 B
Dart
27 lines
754 B
Dart
import 'dart:typed_data';
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import 'asn1_identifier.dart';
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class ASN1DEREncoder {
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static Uint8List encodeSequence({required Uint8List content}) {
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var encoded = Uint8List.fromList([]);
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encoded.add(ASN1Identifier.constructedTag |
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ASN1IdentifierTagNumber.SEQUENCE.toValue());
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encoded.addAll(contentLength(size: content.length));
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encoded.addAll(content);
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return Uint8List.fromList(encoded);
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}
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static Uint8List contentLength({required int size}) {
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if (size >= 128) {
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var lenBytes = Uint8List(size);
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while (lenBytes.first == 0) {
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lenBytes.removeAt(0);
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}
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int len = 0x80 | lenBytes.length;
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return Uint8List(len)..addAll(lenBytes);
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} else {
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return Uint8List(size);
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}
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}
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}
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