LibHac/hactoolnet/ProcessNsp.cs

using System.IO;
using System.Reflection;
using LibHac;

namespace hactoolnet
{
    internal static class ProcessNsp
    {
        public static void CreateNsp(Context ctx, SwitchFs switchFs)
        {
            var id = ctx.Options.TitleId;
            if (id == 0)
            {
                ctx.Logger.LogMessage("Title ID must be specified to save title");
                return;
            }

            if (!switchFs.Titles.TryGetValue(id, out var title))
            {
                ctx.Logger.LogMessage($"Could not find title {id:X16}");
                return;
            }

            var builder = new Pfs0Builder();

            foreach (var nca in title.Ncas)
            {
                builder.AddFile(nca.Filename, nca.GetStream());
            }

            var ticket = new Ticket
            {
                SignatureType = TicketSigType.Rsa2048Sha256,
                Signature = new byte[0x200],
                Issuer = "Root-CA00000003-XS00000020",
                FormatVersion = 2,
                RightsId = title.MainNca.Header.RightsId,
                TitleKeyBlock = title.MainNca.TitleKey,
                CryptoType = title.MainNca.Header.CryptoType2,
                SectHeaderOffset = 0x2C0
            };
            var ticketBytes = ticket.GetBytes();
            builder.AddFile($"{ticket.RightsId.ToHexString()}.tik", new MemoryStream(ticketBytes));

            var thisAssembly = Assembly.GetExecutingAssembly();
            var cert = thisAssembly.GetManifestResourceStream("hactoolnet.CA00000003_XS00000020");
            builder.AddFile($"{ticket.RightsId.ToHexString()}.cert", cert);


            using (var outStream = new FileStream(ctx.Options.NspOut, FileMode.Create, FileAccess.ReadWrite))
            {
                builder.Build(outStream, ctx.Logger);
            }
        }
    }
}