ASN1Swift provides a transparent interface to decode ASN.1 data structures. The ASN.1 Data Structure must be encoded using BER/DER Encoding Rules. To simplify encoding and decoding process ASN1Swift implement Encoder/Decoder protocol provided by swift foundation. In other words it works preciesly the same as JSONEncoder/JSONDecoder.

Installation

CocoaPods

To integrate ASN1Swift into your project using CocoaPods, specify it in your Podfile:

platform :ios, '13.0'

target 'YOUR_TARGET' do
use_frameworks!

pod 'ASN1Swift'
end

Then, run the following command:

$ pod install

In any swift file you’d like to use ASN1Swift, import the framework with import ASN1Swift.

Swift Package Manager

To integrate using Apple’s Swift package manager, add the following as a dependency to your Package.swift:

.package(url: "https://github.com/tikhop/ASN1Swift.git", .branch("master"))

Then, specify "ASN1Swift" as a dependency of the Target in which you wish to use ASN1Swift.

Lastly, run the following command:

swift package update

Carthage

Make the following entry in your Cartfile:

github "tikhop/ASN1Swift" 

Then run carthage update.

If this is your first time using Carthage in the project, you’ll need to go through some additional steps as explained over at Carthage.

Requirements

• iOS 10.0+ / OSX 10.11+
• Swift 5.2+

Example

Decoding InAppReceipt

let asn1Decoder = ASN1Decoder()
let r = try! asn1Decoder.decode(Receipt.self, from: Data(...))

struct Receipt: ASN1Decodable
{
    static var template: ASN1Template
    {
        return ASN1Template.universal(16).constructed()
    }

    var oid: ASN1SkippedField
    var signedData: SignedData

    enum CodingKeys: ASN1CodingKey
    {
        case oid
        case signedData

        var template: ASN1Template
        {
            switch self
            {
                case .oid:
                    return .universal(ASN1Identifier.Tag.objectIdentifier)
                case .signedData:
                    return SignedData.template
            }
        }
    }
}

....

Benchmarks

Library	Decoding Time
ASN1Swift	0.154 seconds
filom/ASN1Decoder	1.032 seconds
asn1c	???
mrdepth/ASN1Decoder	???

License

ASN1Swift is released under a BSD-3-Clause. See LICENSE for more information.