Metadata-Version: 2.1
Name: nsz
Version: 2.1
Summary: NSZ - Homebrew compatible NSP/XCI compressor/decompressor
Home-page: https://github.com/nicoboss/nsz
Author: Nico Bosshard
Author-email: nico@bosshome.ch
Maintainer: Nico Bosshard
Maintainer-email: nico@bosshome.ch
License: UNKNOWN
Description: ## NSZ
        NSZ files are not a real format, they are functionally identical to NSP files. Their sole purpose to alert the user that it contains compressed NCZ files. NCZ files can be mixed with NCA files in the same container.
        
        NSC_Builder supports compressing NSP to NSZ, and decompressing NSZ to NSP. The sample scripts located here are just examples of how the format works.
        
        NSC_Builder can be downloaded at https://github.com/julesontheroad/NSC_BUILDER
        
        ## XCZ
        XCZ files are not a real format, they are functionally identical to XCI files. Their sole purpose to alert the user that it contains compressed NCZ files. NCZ files can be mixed with NCA files in the same container.
        
        ## NCZ
        These are compressed NCA files. The NCA's are decrypted, and then compressed using zStandard. Only NCA's with a 0x4000 byte header are supported (CNMT nca's are not supported).
        
        The first 0x4000 bytes of a NCZ file is exactly the same as the original NCA (and still encrypted).
        
        At 0x4000, there is the variable sized NCZ Header. It contains a list of sections which tell the decompressor how to re-encrypt the NCA data after decompression. It can also contain an optional block compression header allowing random read access.
        
        All of the information in the header can be derived from the original NCA + Ticket, however it is provided preparsed to make decompression as easy as possible for third parties.
        
        Directly after the NCZ header, the zStandard stream begins and ends at EOF. The stream is decompressed to offset 0x4000. If block compression is used the stream is splatted into independent blocks and can be decompressed as shown in https://github.com/nicoboss/nsz/blob/master/nsz/BlockDecompressorReader.py
        
        ```python
        class Section:
        	def __init__(self, f):
        		self.magic = f.read(8) # b'NCZSECTN'
        		self.offset = f.readInt64()
        		self.size = f.readInt64()
        		self.cryptoType = f.readInt64()
        		f.readInt64() # padding
        		self.cryptoKey = f.read(16)
        		self.cryptoCounter = f.read(16)
        
        class Block:
        	def __init__(self, f):
        		self.magic = f.read(8) # b'NCZBLOCK'
        		self.version = f.readInt8()
        		self.type = f.readInt8()
        		self.unused = f.readInt8()
        		self.blockSizeExponent = f.readInt8()
        		self.numberOfBlocks = f.readInt32()
        		self.decompressedSize = f.readInt64()
        		self.compressedBlockSizeList = []
        		for i in range(self.numberOfBlocks):
        			self.compressedBlockSizeList.append(f.readInt32())
        
        nspf.seek(0x4000)
        sectionCount = nspf.readInt64()
        for i in range(sectionCount):
        	sections.append(Section(nspf))
        
        if blockCompression:
        	BlockHeader = Block(nspf)
        ```
        
        ## How to install
        
        Install Python from<br/>
        pip install nsz<br/>
        
        or just use the windows portable builds.<br/>
        
        To manually install dependencies use:<br/>
        pip install -r requirements.txt
        
        To update just use:<br/>
        pip install nsz --upgrade<br/>
        or download the latest windows portable build
        ## Compressor script
        
        Requires latest hactool compatible prod.keys at<br/>
        Windows: %userprofile%\.switch\ (enter .switch. as foldername to get a folder named .switch)<br/>
        Linux: $HOME/.switch/<br/>
        or keys.txt at the location of nsz.py/nsz.exe<br/>
        Please dump your keys using https://github.com/shchmue/Lockpick_RCM/releases<br/>
        Always keep your keys up to date as otherwise newer games can't be decrypted anymore.<br/>
        
        Example usage:<br/>
        nsz --level 18 -C title1.nsp title2.nsp title3.nsp<br/>
        will generate title1.nsz title2.nsz title3.nsz<br/>
        
        This tool was only tested with base games, updates and DLCs.<br/>
        
        ## Usage
        ```
        nsz.py --help
        usage: nsz.py [-h] [-C] [-D] [-l LEVEL] [-B] [-s BS] [-V] [-p] [-t THREADS]
                      [-o OUTPUT] [-w] [-r] [-i INFO] [--depth DEPTH]
                      [-x EXTRACT [EXTRACT ...]] [-c CREATE] [--rm-source]
                      [file [file ...]]
        
        positional arguments:
          file
        
        optional arguments:
          -h, --help            show this help message and exit
          -C                    Compress NSP
          -D                    Decompress NSZ
          -l LEVEL, --level LEVEL
                                Compression Level
          -B, --block           Uses highly multithreaded block compression with
                                random read access allowing compressed games to be
                                played without decompression in the future however
                                this comes with a low compression ratio cost. Current
                                title installers do not support this yet.
          -s BS, --bs BS        Block Size for random read access 2^x while x between
                                14 and 32. Default is 20 => 1 MB. Current title
                                installers do not support this yet.
          -V, --verify          Verifies files after compression raising an unhandled
                                exception on hash mismatch and verify existing NSP and
                                NSZ files when given as parameter
          -p, --parseCnmt       Extract TitleId/Version from Cnmt if this information
                                cannot be obtained from the filename. Required for
                                skipping/overwriting existing files and --rm-old-
                                version to work properly if some not every file is
                                named properly. Supported filenames:
                                *TitleID*[vVersion]*
          -t THREADS, --threads THREADS
                                Number of threads to compress with. Numbers < 1
                                corresponds to the number of logical CPU cores.
          -o OUTPUT, --output OUTPUT
                                Directory to save the output NSZ files
          -w, --overwrite       Continues even if there already is a file with the
                                same name or title id inside the output directory
          -r, --rm-old-version  Removes older version if found
          -i INFO, --info INFO  Show info about title or file
          --depth DEPTH         Max depth for file info and extraction
          -x EXTRACT [EXTRACT ...], --extract EXTRACT [EXTRACT ...]
                                extract / unpack a NSP
          -c CREATE, --create CREATE
                                create / pack a NSP
          --rm-source           Deletes source file/s after compressing/decompressing.
                                It's recommended to only use this in combination with
                                --verify
        ```
        
        ## Credits
        
        SciresM for his hardware crypto functions; the blazing install speeds (50 MB/sec +) achieved here would not be possible without this.
        
        
Keywords: nsz,xcz,ncz,nsp,xci
Platform: UNKNOWN
Classifier: Programming Language :: Python :: 3
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Requires-Python: >=3.6
Description-Content-Type: text/markdown
