Handle cert chain data in a title as a CertificateChain instead of bytes

src/libWiiPy/title/nus.py

@@ -40,10 +40,10 @@ def download_title(title_id: str, title_version: int = None, wiiu_endpoint: bool
     """
     # First, create the new title.
     title = Title()
-    # Download and load the TMD, Ticket, and certs.
+    # Download and load the certificate chain, TMD, and Ticket.
+    title.load_cert_chain(download_cert_chain(wiiu_endpoint, endpoint_override))
     title.load_tmd(download_tmd(title_id, title_version, wiiu_endpoint, endpoint_override))
     title.load_ticket(download_ticket(title_id, wiiu_endpoint, endpoint_override))
-    title.wad.set_cert_data(download_cert(wiiu_endpoint, endpoint_override))
     # Download all contents
     title.load_content_records()
     title.content.content_list = download_contents(title_id, title.tmd, wiiu_endpoint, endpoint_override)
@@ -146,9 +146,9 @@ def download_ticket(title_id: str, wiiu_endpoint: bool = False, endpoint_overrid
     return ticket
 
 
-def download_cert(wiiu_endpoint: bool = False, endpoint_override: str = None) -> bytes:
+def download_cert_chain(wiiu_endpoint: bool = False, endpoint_override: str = None) -> bytes:
     """
-    Downloads the signing certificate used by all WADs. This uses System Menu 4.3U as the source.
+    Downloads the signing certificate chain used by all WADs. This uses System Menu 4.3U as the source.
 
     Parameters
     ----------
@@ -163,7 +163,7 @@ def download_cert(wiiu_endpoint: bool = False, endpoint_override: str = None) ->
     bytes
         The cert file.
     """
-    # Download the TMD and cetk for the System Menu 4.3U.
+    # Download the TMD and cetk for System Menu 4.3U (v513).
     if endpoint_override is not None:
         endpoint_url = _validate_endpoint(endpoint_override)
     else:
@@ -175,18 +175,18 @@ def download_cert(wiiu_endpoint: bool = False, endpoint_override: str = None) ->
     cetk_url = endpoint_url + "0000000100000002/cetk"
     tmd = requests.get(url=tmd_url, headers={'User-Agent': 'wii libnup/1.0'}, stream=True).content
     cetk = requests.get(url=cetk_url, headers={'User-Agent': 'wii libnup/1.0'}, stream=True).content
-    # Assemble the certificate.
+    # Assemble the certificate chain.
-    cert = b''
+    cert_chain = b''
     # Certificate Authority data.
-    cert += cetk[0x2A4 + 768:]
+    cert_chain += cetk[0x2A4 + 768:]
-    # Certificate Policy data.
+    # Certificate Policy (TMD certificate) data.
-    cert += tmd[0x328:0x328 + 768]
+    cert_chain += tmd[0x328:0x328 + 768]
-    # XS data.
+    # XS (Ticket certificate) data.
-    cert += cetk[0x2A4:0x2A4 + 768]
+    cert_chain += cetk[0x2A4:0x2A4 + 768]
-    # Since the cert is always the same, check the hash to make sure nothing went wildly wrong.
+    # Since the cert chain is always the same, check the hash to make sure nothing went wildly wrong.
-    if hashlib.sha1(cert).hexdigest() != "ace0f15d2a851c383fe4657afc3840d6ffe30ad0":
+    if hashlib.sha1(cert_chain).hexdigest() != "ace0f15d2a851c383fe4657afc3840d6ffe30ad0":
         raise Exception("An unknown error has occurred downloading and creating the certificate.")
-    return cert
+    return cert_chain
 
 
 def download_content(title_id: str, content_id: int, wiiu_endpoint: bool = False,

src/libWiiPy/title/title.py

@@ -4,6 +4,7 @@
 # See https://wiibrew.org/wiki/Title for details about how titles are formatted
 
 import math
+from .cert import CertificateChain
 from .content import ContentRegion
 from .ticket import Ticket
 from .tmd import TMD
@@ -21,6 +22,8 @@ class Title:
     ----------
     wad: WAD
         A WAD object of a WAD containing the title's data.
+    cert_chain: CertificateChain
+        The chain of certificates used to verify the contents of a title.
     tmd: TMD
         A TMD object of the title's TMD.
     ticket: Ticket
@@ -30,6 +33,7 @@ class Title:
     """
     def __init__(self):
         self.wad: WAD = WAD()
+        self.cert_chain: CertificateChain = CertificateChain()
         self.tmd: TMD = TMD()
         self.ticket: Ticket = Ticket()
         self.content: ContentRegion = ContentRegion()
@@ -47,6 +51,9 @@ class Title:
         # Create a new WAD object based on the WAD data provided.
         self.wad = WAD()
         self.wad.load(wad)
+        # Load the certificate chain.
+        self.cert_chain = CertificateChain()
+        self.cert_chain.load(self.wad.get_cert_data())
         # Load the TMD.
         self.tmd = TMD()
         self.tmd.load(self.wad.get_tmd_data())
@@ -75,6 +82,8 @@ class Title:
         # Set WAD type to ib if the title being packed is boot2.
         if self.tmd.title_id == "0000000100000001":
             self.wad.wad_type = "ib"
+        # Dump the certificate chain and set it in the WAD.
+        self.wad.set_cert_data(self.cert_chain.dump())
         # Dump the TMD and set it in the WAD.
         # This requires updating the content records and number of contents in the TMD first.
         self.tmd.content_records = self.content.content_records  # This may not be needed because it's a ref already
@@ -87,6 +96,19 @@ class Title:
         self.wad.set_content_data(content_data, content_size)
         return self.wad.dump()
 
+    def load_cert_chain(self, cert_chain: bytes) -> None:
+        """
+        Load an existing certificate chain into the title. Note that this will overwrite any existing certificate chain
+        data for this title.
+
+        Parameters
+        ----------
+        cert_chain: bytes
+            The data for the certificate chain to load.
+        """
+        self.cert_chain.load(cert_chain)
+
+
     def load_tmd(self, tmd: bytes) -> None:
         """
         Load existing TMD data into the title. Note that this will overwrite any existing TMD data for this title.
@@ -94,9 +116,8 @@ class Title:
         Parameters
         ----------
         tmd : bytes
-            The data for the WAD you wish to load.
+            The data for the TMD to load.
         """
-        # Load TMD.
         self.tmd.load(tmd)
 
     def load_ticket(self, ticket: bytes) -> None:
@@ -107,9 +128,8 @@ class Title:
         Parameters
         ----------
         ticket : bytes
-            The data for the WAD you wish to load.
+            The data for the Ticket to load.
         """
-        # Load Ticket.
         self.ticket.load(ticket)
 
     def load_content_records(self) -> None: