LibProsperoPkg

A .NET class library for building and inspecting PS5 packages. It turns a prepared application folder into a complete, installable debug package end to end, in-process, without an external command-line tool.

The library is written in C# 14 and targets .NET 10. It is self-contained and exposes a small, documented public API any .NET application can consume.

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Highlights

• End-to-end pipeline. Folder -> inner PFS layout -> AES-XTS encryption -> outer PFS -> \x7FCNT metadata container -> finalized \x7FFIH debug image, in one process.
• Self-contained. The GP5 project model, the PFS image builder, AES-XTS encryption, RSA-3072 metadata signing and the finalized debug image are produced by the library itself.
• Reader and writer. Parse and inspect existing PS5 packages (\x7FCNT / \x7FFIH) and build new ones.
• Extraction. Extract the application filesystem from a finalized debug/keyed image with ProsperoPackageExtractor, or from any image whose 32-byte image key is supplied.
• Disc-backup packages. Open a split disc backup (the ordered app_0 / app_sc pieces) through its app.json manifest, reassemble it on the fly, and verify the package digest and 64 KiB chunk CRCs.
• License (rif). Read, write and create the per-title license record — including multi-title files — through LibProsperoPkg.License.
• Acceptance checks. Validate a package against the structural gate the console mount path enforces (ProsperoPkgValidator).
• Fake-signed packages (fPKG). Optionally fake-sign raw ELF modules (eboot.bin, *.elf, *.prx, *.sprx) to fake-self before packing, producing an installable fake package. The conversion is non-destructive: source modules are restored after the build.
• Backup conversion. ProsperoBackupConverter repackages a decrypted application backup into a debug fPKG, substituting each executable with its decrypted ELF and fake-signing it, so the image mounts from the content id and passcode with no rif.
• Launch-readiness inspection. ProsperoLaunchReadiness inspects an assembled application root and reports whether it meets the debug-launch conditions: every executable module is a plaintext module the loader accepts, eboot.bin is present, and the metadata is a param.json rather than a PS4 param.sfo.
• Homebrew packaging. ProsperoHomebrewPackager turns a compiled homebrew folder into an installable debug fPKG: it assembles a clean source tree, builds a license-free debug image whose mount key derives from the content id and passcode, and checks launch-readiness. A worked sample lives in src/HomebrewTest.
• Application type. ProsperoApplicationType selects the generated param.json applicationDrmType (free / standard / freemium), covering paid, upgradable, demo and freemium apps.
• Texture generation. The sce_sys icon/picture DDS (BC7) encoder decodes the source PNG and block-compresses it to a DX10 BC7 texture in-process.

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Requirements

Toolchain	.NET 10 SDK or newer
Language	C# 14

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Building

cd LibProsperoPKG/src/LibProsperoPkg
dotnet build -c Release

This produces LibProsperoPkg.dll.

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Quick start

Add the project (or the built LibProsperoPkg.dll) to your build and create a package from a prepared application folder:

using LibProsperoPkg;

var options = new ProsperoBuildOptions
{
    Mode         = ProsperoPackageMode.Application,
    OutputFormat = ProsperoOutputFormat.DebugImage,   // installable on a debug-mode console
    SourceFolder = @"/path/to/prepared/app",          // must contain sce_sys/
    OutputFolder = @"/path/to/output",
    ContentId    = "UP9000-PPSA00000_00-PROSPERO00000000",
    TitleId      = "PPSA00000",
    Title        = "My PS5 Application",
    Version      = "01.00",
};

ProsperoBuildResult result = ProsperoPackageBuilder.Build(options, Console.WriteLine);

Console.WriteLine($"Package written to: {result.OutputPath}");
foreach (var warning in result.Warnings)
    Console.WriteLine($"Warning: {warning}");

Fake-signing modules (fPKG)

Set FakeSignSelfModules to convert raw ELF modules in the source folder to fake-self before packing. Use ApplicationType to control the generated param.json applicationDrmType:

var options = new ProsperoBuildOptions
{
    Mode                = ProsperoPackageMode.Application,
    OutputFormat        = ProsperoOutputFormat.DebugImage,
    SourceFolder        = @"/path/to/prepared/app",
    OutputFolder        = @"/path/to/output",
    ContentId           = "UP9000-PPSA00000_00-PROSPERO00000000",
    TitleId             = "PPSA00000",
    Title               = "My PS5 Application",
    Version             = "01.00",
    ApplicationType     = ProsperoApplicationType.FreemiumApp,
    FakeSignSelfModules = true,
};

Files that are already SELF are left untouched, and the original module bytes are restored once packing completes.

To build a DRM-free, license-free package in one step, set LicenseFree. It fake-signs modules and derives the debug mount key from the content id and passcode, so no rif is written. ProsperoBuildResult.DebugLicense reports the grant and ProsperoBuildResult.LicenseFree echoes the option. The output is a debug finalized image for a debug-enabled console.

To repackage a decrypted application backup into a debug fPKG, call ProsperoBackupConverter.Convert. It substitutes each signed executable with its decrypted raw ELF, fake-signs the modules, and builds a debug image that mounts from the content id and passcode. The backup stays untouched; the converter works from a staging copy.

var result = ProsperoBackupConverter.Convert(new ProsperoBackupConversionOptions
{
    BackupFolder = @"/path/to/backup/PPSA00000-app0",
    OutputFolder = @"/path/to/output",
});

Packaging a homebrew module

To package a compiled homebrew folder (a raw ELF eboot.bin plus an optional sce_sys/ tree) into an installable debug fPKG, call ProsperoHomebrewPackager.Package. It fake-signs the module and derives the mount key from the content id and passcode, then checks launch-readiness. A worked sample lives in src/HomebrewTest.

var result = ProsperoHomebrewPackager.Package(new ProsperoHomebrewPackageOptions
{
    HomebrewFolder = @"/path/to/HomebrewTest",
    OutputFolder   = @"/path/to/output",
    ContentId      = "UP9000-PPSA99099_00-PROSPERO00000000",
    Title          = "LibProsperoPKG",
});
Console.WriteLine($"Launch ready: {result.LaunchReadiness.IsLaunchReady}");

Every build path stores the inner image as the data-first image.

Inspecting an existing package

using LibProsperoPkg.PKG;

ProsperoPkg pkg = ProsperoPkgReader.Read(@"/path/to/package.pkg");
Console.WriteLine($"Type:       {pkg.Type}");
Console.WriteLine($"Content ID: {pkg.Header?.ContentId}");
Console.WriteLine($"Entries:    {pkg.Entries.Count}");

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Public surface, at a glance

Namespace	Key types
LibProsperoPkg	ProsperoPackageBuilder, ProsperoBackupConverter, ProsperoHomebrewPackager, ProsperoBuildOptions, ProsperoBuildResult, ProsperoBackupConversionOptions, ProsperoBackupConversionResult, ProsperoHomebrewPackageOptions, ProsperoHomebrewPackageResult, ProsperoPackageMode, ProsperoOutputFormat, InnerImageForm, ProsperoApplicationType
LibProsperoPkg.PKG	ProsperoPkgBuilder, ProsperoPkgReader, ProsperoCntWriter, ProsperoFihBuilder, ProsperoPkgSigner, ProsperoDdsEncoder, ProsperoPackageExtractor, ProsperoExtractionKey, ProsperoPkgValidator, ProsperoPkg, ProsperoPkgHeader
LibProsperoPkg.PFS	ProsperoPfsLayout, ProsperoPfsImage, ProsperoPfsc, ProsperoPfsExtractor
LibProsperoPkg.License	ProsperoRif, ProsperoRifSet, ProsperoEntitlementKey
LibProsperoPkg.NpDrm	ProsperoNpDrmContentInfo
LibProsperoPkg.DiscBackup	ProsperoDiscBackup, ProsperoDiscBackupManifest, ProsperoPlaygoChunkCrc
LibProsperoPkg.GP5	Gp5Creator, Gp5Project and its element model
LibProsperoPkg.Keys	ProsperoKeys
LibProsperoPkg.PlayGo	ProsperoPlayGo
LibProsperoPkg.Content	ProsperoUcp, ProsperoFself, ProsperoSelfAuthInfo, ProsperoElfHeader, ProsperoLaunchReadiness

See docs/ for the full feature status and the PS5 package technical write-up.

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Documentation

• docs/README.md - documentation index.
• docs/getting-started.md - install, build and first package.
• docs/api-overview.md - public API by namespace.
• docs/implementation-status.md - what is implemented and what is still missing.
• docs/ps5-pkg-format.md - technical write-up of the PS5 package format and the creation process.

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Coverage

LibProsperoPkg produces a complete debug package end to end: the finalized \x7FFIH image, the \x7FCNT metadata container, the inner-image assembly, the layout/metric metadata and the trailing install-metadata archive, all of which round-trip through the reader. A console running in debug mode, which relaxes finalized-image verification, is the intended target. The retail (submitted) image path and the per-console license and key material are gated on console-side material the library does not have. On-console acceptance depends on the console's mode and firmware. See docs/implementation-status.md for the precise breakdown.

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License

LibProsperoPkg is licensed under the GNU General Public License v3.0 or later (GPL-3.0-or-later). See LICENSE. Third-party attributions are listed in NOTICE.