2 files changed, 45 insertions, 3 deletions

diff --git a/src/core/crypto/key_manager.cpp b/src/core/crypto/key_manager.cpp
index e4b33f750..994ac4eec 100644
--- a/src/core/crypto/key_manager.cpp
+++ b/src/core/crypto/key_manager.cpp
@@ -153,17 +153,17 @@ void KeyManager::LoadFromFile(const std::string& filename, bool is_title_keys) {
             u128 rights_id{};
             std::memcpy(rights_id.data(), rights_id_raw.data(), rights_id_raw.size());
             Key128 key = Common::HexStringToArray<16>(out[1]);
-            SetKey(S128KeyType::Titlekey, key, rights_id[1], rights_id[0]);
+            s128_keys[{S128KeyType::Titlekey, rights_id[1], rights_id[0]}] = key;
         } else {
             std::transform(out[0].begin(), out[0].end(), out[0].begin(), ::tolower);
             if (s128_file_id.find(out[0]) != s128_file_id.end()) {
                 const auto index = s128_file_id.at(out[0]);
                 Key128 key = Common::HexStringToArray<16>(out[1]);
-                SetKey(index.type, key, index.field1, index.field2);
+                s128_keys[{index.type, index.field1, index.field2}] = key;
             } else if (s256_file_id.find(out[0]) != s256_file_id.end()) {
                 const auto index = s256_file_id.at(out[0]);
                 Key256 key = Common::HexStringToArray<32>(out[1]);
-                SetKey(index.type, key, index.field1, index.field2);
+                s256_keys[{index.type, index.field1, index.field2}] = key;
             }
         }
     }
@@ -197,11 +197,51 @@ Key256 KeyManager::GetKey(S256KeyType id, u64 field1, u64 field2) const {
     return s256_keys.at({id, field1, field2});
 }
 
+template <size_t Size>
+void KeyManager::WriteKeyToFile(bool title_key, std::string_view keyname,
+                                std::array<u8, Size> key) {
+    const std::string yuzu_keys_dir = FileUtil::GetUserPath(FileUtil::UserPath::KeysDir);
+    std::string filename = "title.keys_autogenerated";
+    if (!title_key)
+        filename = dev_mode ? "dev.keys_autogenerated" : "prod.keys_autogenerated";
+    const auto add_info_text = !FileUtil::Exists(yuzu_keys_dir + DIR_SEP + filename);
+    std::ofstream file(yuzu_keys_dir + DIR_SEP + filename, std::ios::app);
+    if (!file.is_open())
+        return;
+    if (add_info_text) {
+        file << "# This file is autogenerated by Yuzu" << std::endl
+             << "# It serves to store keys that were automatically generated from the normal keys"
+             << std::endl
+             << "# If you are experiencing issues involving keys, it may help to delete this file"
+             << std::endl;
+    }
+
+    file << std::endl
+         << fmt::format("{} = {}", keyname, Common::HexArrayToString(key)) << std::endl;
+    AttemptLoadKeyFile(yuzu_keys_dir, yuzu_keys_dir, filename, title_key);
+}
+
 void KeyManager::SetKey(S128KeyType id, Key128 key, u64 field1, u64 field2) {
+    const auto iter = std::find_if(
+        s128_file_id.begin(), s128_file_id.end(),
+        [&id, &field1, &field2](const std::pair<std::string, KeyIndex<S128KeyType>> elem) {
+            return std::tie(elem.second.type, elem.second.field1, elem.second.field2) ==
+                   std::tie(id, field1, field2);
+        });
+    if (iter != s128_file_id.end())
+        WriteKeyToFile(id == S128KeyType::Titlekey, iter->first, key);
     s128_keys[{id, field1, field2}] = key;
 }
 
 void KeyManager::SetKey(S256KeyType id, Key256 key, u64 field1, u64 field2) {
+    const auto iter = std::find_if(
+        s256_file_id.begin(), s256_file_id.end(),
+        [&id, &field1, &field2](const std::pair<std::string, KeyIndex<S256KeyType>> elem) {
+            return std::tie(elem.second.type, elem.second.field1, elem.second.field2) ==
+                   std::tie(id, field1, field2);
+        });
+    if (iter != s256_file_id.end())
+        WriteKeyToFile(false, iter->first, key);
     s256_keys[{id, field1, field2}] = key;
 }
 
diff --git a/src/core/crypto/key_manager.h b/src/core/crypto/key_manager.h
index 31040dc55..78d0b64e0 100644
--- a/src/core/crypto/key_manager.h
+++ b/src/core/crypto/key_manager.h
@@ -106,6 +106,8 @@ private:
     void LoadFromFile(const std::string& filename, bool is_title_keys);
     void AttemptLoadKeyFile(const std::string& dir1, const std::string& dir2,
                             const std::string& filename, bool title);
+    template <size_t Size>
+    void WriteKeyToFile(bool title_key, std::string_view keyname, std::array<u8, Size> key);
 
     static const boost::container::flat_map<std::string, KeyIndex<S128KeyType>> s128_file_id;
     static const boost::container::flat_map<std::string, KeyIndex<S256KeyType>> s256_file_id;