47 lines
1.6 KiB
Go
47 lines
1.6 KiB
Go
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// Copyright 2017 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package asn1 contains supporting types for parsing and building ASN.1
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// messages with the cryptobyte package.
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package asn1 // import "golang.org/x/crypto/cryptobyte/asn1"
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// Tag represents an ASN.1 identifier octet, consisting of a tag number
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// (indicating a type) and class (such as context-specific or constructed).
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//
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// Methods in the cryptobyte package only support the low-tag-number form, i.e.
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// a single identifier octet with bits 7-8 encoding the class and bits 1-6
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// encoding the tag number.
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type Tag uint8
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const (
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classConstructed = 0x20
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classContextSpecific = 0x80
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)
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// Constructed returns t with the constructed class bit set.
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func (t Tag) Constructed() Tag { return t | classConstructed }
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// ContextSpecific returns t with the context-specific class bit set.
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func (t Tag) ContextSpecific() Tag { return t | classContextSpecific }
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// The following is a list of standard tag and class combinations.
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const (
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BOOLEAN = Tag(1)
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INTEGER = Tag(2)
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BIT_STRING = Tag(3)
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OCTET_STRING = Tag(4)
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NULL = Tag(5)
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OBJECT_IDENTIFIER = Tag(6)
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ENUM = Tag(10)
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UTF8String = Tag(12)
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SEQUENCE = Tag(16 | classConstructed)
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SET = Tag(17 | classConstructed)
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PrintableString = Tag(19)
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T61String = Tag(20)
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IA5String = Tag(22)
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UTCTime = Tag(23)
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GeneralizedTime = Tag(24)
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GeneralString = Tag(27)
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)
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