From 5a57d42c529bc4a4c35ccb33da94f9f2dde4c35f Mon Sep 17 00:00:00 2001
From: Maschell <Maschell@gmx.de>
Date: Fri, 26 Apr 2019 09:51:28 +0200
Subject: [PATCH] Check partial file reads on a different location

---
 .../jnus/implementations/FSTDataProviderNUSTitle.java |  2 +-
 .../wiiu/jnus/utils/cryptography/NUSDecryption.java   | 11 ++++-------
 2 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/src/de/mas/wiiu/jnus/implementations/FSTDataProviderNUSTitle.java b/src/de/mas/wiiu/jnus/implementations/FSTDataProviderNUSTitle.java
index bedc45a..0fded7d 100644
--- a/src/de/mas/wiiu/jnus/implementations/FSTDataProviderNUSTitle.java
+++ b/src/de/mas/wiiu/jnus/implementations/FSTDataProviderNUSTitle.java
@@ -146,7 +146,7 @@ public class FSTDataProviderNUSTitle implements FSTDataProvider, HasNUSTitle {
             if (c.isHashed()) {
                 h3HashedOpt = dataProvider.getContentH3Hash(c);
             }
-            return nusdecryption.decryptStreams(in, outputStream, fileOffset, fileSize, c, h3HashedOpt);
+            return nusdecryption.decryptStreams(in, outputStream, fileOffset, fileSize, c, h3HashedOpt, fileSize == entry.getFileSize());
         } catch (CheckSumWrongException e) {
             if (c.isUNKNWNFlag1Set()) {
                 log.info("Hash doesn't match. But file is optional. Don't worry.");
diff --git a/src/de/mas/wiiu/jnus/utils/cryptography/NUSDecryption.java b/src/de/mas/wiiu/jnus/utils/cryptography/NUSDecryption.java
index 73b2f4c..b9dc0ae 100644
--- a/src/de/mas/wiiu/jnus/utils/cryptography/NUSDecryption.java
+++ b/src/de/mas/wiiu/jnus/utils/cryptography/NUSDecryption.java
@@ -276,8 +276,8 @@ public class NUSDecryption extends AESDecryption {
         return output;
     }
 
-    public boolean decryptStreams(InputStream inputStream, OutputStream outputStream, long offset, long size, Content content, Optional<byte[]> h3HashHashed)
-            throws IOException, CheckSumWrongException, NoSuchAlgorithmException {
+    public boolean decryptStreams(InputStream inputStream, OutputStream outputStream, long offset, long size, Content content, Optional<byte[]> h3HashHashed,
+            boolean partial) throws IOException, CheckSumWrongException, NoSuchAlgorithmException {
 
         short contentIndex = (short) content.getIndex();
 
@@ -290,11 +290,8 @@ public class NUSDecryption extends AESDecryption {
                     decryptFileStreamHashed(inputStream, outputStream, offset, size, (short) contentIndex, h3);
                 } else {
                     byte[] h3Hash = content.getSHA2Hash();
-                    // We want to check if we read the whole file or just a part of it.
-                    // There should be only one actual file inside a non-hashed content.
-                    // But it could also contain a directory, so we need to filter.
-                    long fstFileSize = content.getEntries().stream().filter(f -> !f.isDir()).findFirst().map(f -> f.getFileSize()).orElse(0L);
-                    if (size > 0 && size < fstFileSize) {
+                    // Ignore the h3hash if we don't read the whole file.
+                    if (partial) {
                         h3Hash = null;
                     }
                     decryptFileStream(inputStream, outputStream, offset, size, (short) contentIndex, h3Hash, encryptedFileSize);