Crate bsn1[−][src]

bsn1 treats ‘ASN.1.’

What is ASN.1?

ASN.1 stands for ‘Abstruct Syntax Notation One’ and X.690 is an ‘ITU-T’ standard specifying the following ASN.1 encording formats.

Basic Encoding Rules (BER)
Canonical Encoding Rules (CER)
Distinguished Encoding Rules (DER)

This crate supports BER and DER so far.

ASN.1 formats resembles ‘JSON’ in some ways, because they both are about serializing structured data, however, they differs in the following points.

JSON are easy for human to read, on the other hand, ASN.1 is readable for a computer. i.e. ASN.1 consumes less computer resources and less CPU time than JSON does.
ASN.1 defines types ‘Integer’, ‘Boolean’, ‘String’, ‘Sequence’, and so on universally like JSON. What is more, ASN.1 allows for users to define a new data type.

ASN.1 has been used all over the world for a long time and very stable. For example, ‘Transport Layer Security (TLS, SSL)’, ‘Lightweight Directory Access Protocol (LDAP)’, ‘4th Generation Mobile Communication System (4G)’, and so on.

See ‘X.690 (07/2002)’ for details.

Feature of `bsn1`

bsn1 treats user defined data as well as universal data types; while most other rust crates can treat only universal data.

To be accurate, there are 4 classes in ASN.1; universal class, application class, context specific class, and private class. bsn1 knows all of them.

Modules

contents

Provides functions to serialize/deserialize contents octets.

Macros

constructed_ber	Builds a `Ber` instance representing Constructed BER effectively.
constructed_der	Builds a `Der` instance representing ‘Constructed DER’ effectively.

Structs

Ber	`Ber` owns `BerRef` and represents a BER.
BerBuilder	`BerBuilder` is a struct to build `Ber` effectively.
BerRef	`BerRef` is a wrapper of `[u8]` and represents a BER.
Der	`Der` owns `DerRef` and represents DER.
DerBuilder	`DerBuilder` is a struct to build `Der` effectively.
DerRef	`DerRef` is a wrapper of `[u8]` and represents DER.
Id	`Id` owns `IdRef` and represents Identifier.
IdRef	`IdRef` is a wrapper of `[u8]` represents Identifier.

Enums

ClassTag	`ClassTag` represents Tag class of identifier.
Error	Errors for this crate.
Length	`Length` represents ASN.1 length.
PCTag	`PCTag` represents Private/Constructed flag of identifier.

Functions

length_to_bytes	Serializes `length` .
try_length_from	Tries to parse `bytes` starting with ‘length’ and returns `Length` .