BasicConstraints.cs

using System;
 
namespace NeuroAccess.Nfc.TravelDocuments.Security.Properties.CertificateExtensions
{
    public class BasicConstraints : SecurityObject
    {
        private bool certificateAuthority = false;
        private int pathLengthConstraint = int.MaxValue;
        private KeyUsage? keyUsage = null;
        protected bool configured;
 
        public override string Oid => "2.5.29.19";
 
        public override bool IsConfigured => this.configured;
 
        public override bool Configure(Vector SecurityInfo)
        {
            if (SecurityInfo.LastElementNested is Vector BasicConstraints)
            {
                int c = BasicConstraints.Length;
                int i = 0;
 
                if (i < c && BasicConstraints[i] is KeyUsage KeyUsage)
                {
                    i++;
                    this.keyUsage = KeyUsage;
                }
 
                if (i < c && BasicConstraints[i] is bool CertificateAuthority)
                {
                    i++;
                    this.certificateAuthority = CertificateAuthority;
                }
 
                if (i < c && BasicConstraints[i] is System.Numerics.BigInteger PathLengthConstraint &&
                    PathLengthConstraint >= int.MinValue &&
                    PathLengthConstraint <= int.MaxValue)
                {
                    i++;
                    this.pathLengthConstraint = (int)PathLengthConstraint;
                }
 
                if (i < c)
                    return false;
 
                this.configured = true;
 
                return true;
            }
            else if (SecurityInfo.LastElement is null ||
                (SecurityInfo.LastElement is Array A && A.Length == 0))
            {
                this.configured = true;
                return true;
            }
            else
                return false;
        }
 
        public bool CertificateAuthority => this.certificateAuthority;
 
        public int PathLengthConstraint => this.pathLengthConstraint;
 
        public KeyUsage? KeyUsage => this.keyUsage;
    }
}