Merge pull request #17 from NinjaCheetah/nus_download

Add NUS Downloading

README.md

@@ -10,6 +10,7 @@ libWiiPy is inspired by [libWiiSharp](https://github.com/TheShadowEevee/libWiiSh
 This list will expand as libWiiPy is developed, but these features are currently available:
 - TMD, ticket, and WAD parsing
 - WAD content extraction, decryption, re-encryption, and packing
+- Downloading free titles from the NUS
 
 # Usage
 A wiki, and in the future a potential documenation site, is being worked on, and can be accessed [here](https://github.com/NinjaCheetah/libWiiPy/wiki). It is currently fairly barebones, but it will be improved in the future.

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "libWiiPy"
-version = "0.2.0"
+version = "0.2.1"
 authors = [
     { name="NinjaCheetah", email="ninjacheetah@ncxprogramming.com" },
     { name="Lillian Skinner", email="lillian@randommeaninglesscharacters.com" }
@@ -15,6 +15,7 @@ classifiers = [
 ]
 dependencies = [
     "pycryptodome",
+    "urllib3"
 ]
 
 [project.urls]

requirements.txt

@@ -1,2 +1,3 @@
 build
 pycryptodome
+urllib3

src/libWiiPy/__init__.py

@@ -9,3 +9,4 @@ from .ticket import *
 from .title import *
 from .tmd import *
 from .wad import *
+from .nus import *

src/libWiiPy/nus.py

@@ -0,0 +1,205 @@
+# "nus.py" from libWiiPy by NinjaCheetah & Contributors
+# https://github.com/NinjaCheetah/libWiiPy
+#
+# See https://wiibrew.org/wiki/NUS for details about the NUS
+
+import io
+import urllib3
+import hashlib
+from typing import List
+from .title import Title
+from .tmd import TMD
+from .ticket import Ticket
+
+
+def download_title(title_id: str, title_version: int = None) -> Title:
+    """
+    Download an entire title and all of its contents, then load the downloaded components into a Title object for
+    further use. This method is NOT recommended for general use, as it has absolutely no verbosity. It is instead
+    recommended to call the individual download methods instead to provide more flexibility and output.
+
+    Parameters
+    ----------
+    title_id : str
+        The Title ID of the title to download.
+    title_version : int, option
+        The version of the title to download. Defaults to latest if not set.
+
+    Returns
+    -------
+    Title
+        A Title object containing all the data from the downloaded title.
+    """
+    # First, create the new title.
+    title = Title()
+    # Download and load the TMD, Ticket, and certs.
+    title.load_tmd(download_tmd(title_id, title_version))
+    title.load_ticket(download_ticket(title_id))
+    title.wad.set_cert_data(download_cert())
+    # Download all contents
+    title.load_content_records()
+    title.content.content_list = download_contents(title_id, title.tmd)
+    # Return the completed title.
+    return title
+
+
+def download_tmd(title_id: str, title_version: int = None) -> bytes:
+    """
+    Downloads the TMD of the Title specified in the object. Will download the latest version by default, or another
+    version if it was manually specified in the object.
+
+    Parameters
+    ----------
+    title_id : str
+        The Title ID of the title to download the TMD for.
+    title_version : int, option
+        The version of the TMD to download. Defaults to latest if not set.
+
+    Returns
+    -------
+    bytes
+        The TMD file from the NUS.
+    """
+    # Build the download URL. The structure is download/<TID>/tmd for latest and download/<TID>/tmd.<version> for
+    # when a specific version is requested.
+    tmd_url = "http://ccs.shop.wii.com/ccs/download/" + title_id + "/tmd"
+    # Add the version to the URL if one was specified.
+    if title_version is not None:
+        tmd_url += "." + str(title_version)
+    # Make the request.
+    tmd_response = urllib3.request(method='GET', url=tmd_url, headers={'User-Agent': 'wii libnup/1.0'})
+    # Handle a 404 if the TID/version doesn't exist.
+    if tmd_response.status != 200:
+        raise ValueError("The requested Title ID or TMD version does not exist. Please check the Title ID and Title"
+                         " version and then try again.")
+    # Save the raw TMD.
+    raw_tmd = tmd_response.data
+    # Use a TMD object to load the data and then return only the actual TMD.
+    tmd_temp = TMD()
+    tmd_temp.load(raw_tmd)
+    tmd = tmd_temp.dump()
+    return tmd
+
+
+def download_ticket(title_id: str) -> bytes:
+    """
+    Downloads the Ticket of the Title specified in the object. This will only work if the Title ID specified is for
+    a free title.
+
+    Parameters
+    ----------
+    title_id : str
+        The Title ID of the title to download the Ticket for.
+
+    Returns
+    -------
+    bytes
+        The Ticket file from the NUS.
+    """
+    # Build the download URL. The structure is download/<TID>/cetk, and cetk will only exist if this is a free
+    # title.
+    ticket_url = "http://ccs.shop.wii.com/ccs/download/" + title_id + "/cetk"
+    # Make the request.
+    ticket_response = urllib3.request(method='GET', url=ticket_url, headers={'User-Agent': 'wii libnup/1.0'})
+    if ticket_response.status != 200:
+        raise ValueError("The requested Title ID does not exist, or refers to a non-free title. Tickets can only"
+                         " be downloaded for titles that are free on the NUS.")
+    # Save the raw cetk file.
+    cetk = ticket_response.data
+    # Use a Ticket object to load only the Ticket data from cetk and return it.
+    ticket_temp = Ticket()
+    ticket_temp.load(cetk)
+    ticket = ticket_temp.dump()
+    return ticket
+
+
+def download_cert() -> bytes:
+    """
+    Downloads the signing certificate used by all WADs. This uses System Menu 4.3U as the source.
+
+    Returns
+    -------
+    bytes
+        The cert file.
+    """
+    # Download the TMD and cetk for the System Menu 4.3U.
+    tmd = urllib3.request(method='GET', url='http://ccs.shop.wii.com/ccs/download/0000000100000002/tmd.513',
+                          headers={'User-Agent': 'wii libnup/1.0'}).data
+    cetk = urllib3.request(method='GET', url='http://ccs.shop.wii.com/ccs/download/0000000100000002/cetk',
+                           headers={'User-Agent': 'wii libnup/1.0'}).data
+    # Assemble the certificate.
+    with io.BytesIO() as cert_data:
+        # Certificate Authority data.
+        cert_data.write(cetk[0x2A4 + 768:])
+        # Certificate Policy data.
+        cert_data.write(tmd[0x328:0x328 + 768])
+        # XS data.
+        cert_data.write(cetk[0x2A4:0x2A4 + 768])
+        cert_data.seek(0x0)
+        cert = cert_data.read()
+    # Since the cert is always the same, check the hash to make sure nothing went wildly wrong.
+    if hashlib.sha1(cert).hexdigest() != "ace0f15d2a851c383fe4657afc3840d6ffe30ad0":
+        raise Exception("An unknown error has occurred downloading and creating the certificate.")
+    return cert
+
+
+def download_content(title_id: str, content_id: int) -> bytes:
+    """
+    Downloads a specified content for the title specified in the object.
+
+    Parameters
+    ----------
+    title_id : str
+        The Title ID of the title to download content from.
+    content_id : int
+        The Content ID of the content you wish to download.
+
+    Returns
+    -------
+    bytes
+        The downloaded content.
+    """
+    # Build the download URL. The structure is download/<TID>/<Content ID>.
+    content_id_hex = hex(content_id)[2:]
+    if len(content_id_hex) < 2:
+        content_id_hex = "0" + content_id_hex
+    content_url = "http://ccs.shop.wii.com/ccs/download/" + title_id + "/000000" + content_id_hex
+    # Make the request.
+    content_response = urllib3.request(method='GET', url=content_url, headers={'User-Agent': 'wii libnup/1.0'})
+    if content_response.status != 200:
+        raise ValueError("The requested Title ID does not exist, or an invalid Content ID is present in the"
+                         " content records provided.\n Failed while downloading Content ID: 000000" +
+                         content_id_hex)
+    return content_response.data
+
+
+def download_contents(title_id: str, tmd: TMD) -> List[bytes]:
+    """
+    Downloads all the contents for the title specified in the object. This requires a TMD to already be available
+    so that the content records can be accessed.
+
+    Parameters
+    ----------
+    title_id : str
+        The Title ID of the title to download content from.
+    tmd : TMD
+        The TMD that matches the title that the contents being downloaded are from.
+
+    Returns
+    -------
+    List[bytes]
+        A list of all the downloaded contents.
+    """
+    # Retrieve the content records from the TMD.
+    content_records = tmd.content_records
+    # Create a list of Content IDs to download.
+    content_ids = []
+    for content_record in content_records:
+        content_ids.append(content_record.content_id)
+    # Iterate over that list and download each content in it, then add it to the array of contents.
+    content_list = []
+    for content_id in content_ids:
+        # Call self.download_content() for each Content ID.
+        content = download_content(title_id, content_id)
+        content_list.append(content)
+    return content_list