PackageUrlValidator.cs

using System;
using System.Threading.Tasks;
using Waher.Content.Xml;
using Waher.Networking.HTTP;
using Waher.Security;
 
namespace Waher.Service.IoTBroker.Provisioning.SoftwareUpdates
{
    public class PackageUrlValidator : HttpAuthenticationScheme
    {
        public PackageUrlValidator()
        {
        }
 
        public override string GetChallenge()
        {
            throw new BadRequestException();
        }
 
        public override async Task<IUser> IsAuthenticated(HttpRequest Request)
        {
            if (!Request.Header.TryGetQueryParameter("s", out string SignatureStr) ||
                !Request.Header.TryGetQueryParameter("p", out string PublishedStr) ||
                XML.TryParse(PublishedStr, out DateTime Published))
            {
                return null;
            }
 
            Package Package = await ProvisioningComponent.GetPackage(Request.SubPath);
            if (Package is null ||
                Package.Published != Published ||
                string.Compare(Convert.ToBase64String(Package.Signature), SignatureStr, true) != 0)
            {
                return null;
            }
 
            return new PackageUser(Package);
        }
 
        private class PackageUser : IUser
        {
            private readonly Package package;
 
            public PackageUser(Package Package)
            {
                this.package = Package;
            }
 
            public string UserName => this.package.FileName;
            public string PasswordHash => throw new InvalidOperationException();
            public string PasswordHashType => throw new InvalidOperationException();
 
            public bool HasPrivilege(string Privilege)
            {
                return false;
            }
        }
    }
}