Add padding to NCA files over USB transmission

include/install/usb_nsp.hpp

@@ -5,6 +5,9 @@
 
 namespace tin::install::nsp
 {
+    static const size_t PADDING_SIZE = 0x1000;
+    static const u32 CMD_ID_FILE_RANGE = 1;
+    static const u32 CMD_ID_FILE_RANGE_PADDED = 2;
     class USBNSP : public RemoteNSP
     {
         private:

include/util/usb_util.hpp

@@ -30,7 +30,7 @@ namespace tin::util
             static void SendCmdHeader(u32 cmdId, size_t dataSize);
 
             static void SendExitCmd();
-            static USBCmdHeader SendFileRangeCmd(std::string nspName, u64 offset, u64 size);
+            static USBCmdHeader SendFileRangeCmd(u32 cmdId, std::string nspName, u64 offset, u64 size);
     };
 
     size_t USBRead(void* out, size_t len);

source/install/usb_nsp.cpp

@@ -36,17 +36,22 @@ namespace tin::install::nsp
     int USBThreadFunc(void* in)
     {
         USBFuncArgs* args = reinterpret_cast<USBFuncArgs*>(in);
-        tin::util::USBCmdHeader header = tin::util::USBCmdManager::SendFileRangeCmd(args->nspName, args->pfs0Offset, args->ncaSize);
+        tin::util::USBCmdHeader header = tin::util::USBCmdManager::SendFileRangeCmd(CMD_ID_FILE_RANGE_PADDED, args->nspName, args->pfs0Offset, args->ncaSize);
 
-        u8* buf = (u8*)memalign(0x1000, 0x100000);
+        u8* buf = (u8*)memalign(0x1000, tin::data::BUFFER_SEGMENT_DATA_SIZE);
         u64 sizeRemaining = header.dataSize;
         size_t tmpSizeRead = 0;
 
         try
         {
             while (sizeRemaining)
             {
-                tmpSizeRead = usbCommsRead(buf, std::min(sizeRemaining, (u64)0x100000));
+                size_t padding = 0;
+                if (header.cmdId == CMD_ID_FILE_RANGE_PADDED) {
+                    padding = PADDING_SIZE;
+                }
+
+                tmpSizeRead = usbCommsRead(buf, std::min(sizeRemaining + padding, tin::data::BUFFER_SEGMENT_DATA_SIZE)) - padding;
                 //LOG_DEBUG("Read bytes\n")
                 //printBytes(nxlinkout, buf, tmpSizeRead, true);
                 sizeRemaining -= tmpSizeRead;
@@ -57,7 +62,7 @@ namespace tin::install::nsp
                         break;
                 }
 
-                args->bufferedPlaceholderWriter->AppendData(buf, tmpSizeRead);
+                args->bufferedPlaceholderWriter->AppendData(buf + padding, tmpSizeRead);
             }
         }
         catch (std::exception& e)
@@ -151,7 +156,7 @@ namespace tin::install::nsp
 
     void USBNSP::BufferData(void* buf, off_t offset, size_t size)
     {
-        tin::util::USBCmdHeader header = tin::util::USBCmdManager::SendFileRangeCmd(m_nspName, offset, size);
+        tin::util::USBCmdHeader header = tin::util::USBCmdManager::SendFileRangeCmd(CMD_ID_FILE_RANGE, m_nspName, offset, size);
         tin::util::USBRead(buf, header.dataSize);
     }
 }

source/util/usb_util.cpp

@@ -22,7 +22,7 @@ namespace tin::util
         USBCmdManager::SendCmdHeader(0, 0);
     }
 
-    USBCmdHeader USBCmdManager::SendFileRangeCmd(std::string nspName, u64 offset, u64 size)
+    USBCmdHeader USBCmdManager::SendFileRangeCmd(u32 cmdId, std::string nspName, u64 offset, u64 size)
     {
         struct FileRangeCmdHeader
         {
@@ -37,7 +37,7 @@ namespace tin::util
         fRangeHeader.nspNameLen = nspName.size();
         fRangeHeader.padding = 0;
 
-        USBCmdManager::SendCmdHeader(1, sizeof(FileRangeCmdHeader) + fRangeHeader.nspNameLen);
+        USBCmdManager::SendCmdHeader(cmdId, sizeof(FileRangeCmdHeader) + fRangeHeader.nspNameLen);
         USBWrite(&fRangeHeader, sizeof(FileRangeCmdHeader));
         USBWrite(nspName.c_str(), fRangeHeader.nspNameLen);
 

tools/usb_install_pc.py

@@ -33,9 +33,13 @@
 
 CMD_ID_EXIT = 0
 CMD_ID_FILE_RANGE = 1
+CMD_ID_FILE_RANGE_PADDED = 2
 
 CMD_TYPE_RESPONSE = 1
 
+BUFFER_SEGMENT_DATA_SIZE = 0x100000
+PADDING_SIZE = 0x1000
+
 def send_response_header(out_ep, cmd_id, data_size):
     out_ep.write(b'TUC0') # Tinfoil USB Command 0
     out_ep.write(struct.pack('<B', CMD_TYPE_RESPONSE))
@@ -44,7 +48,7 @@ def send_response_header(out_ep, cmd_id, data_size):
     out_ep.write(struct.pack('<Q', data_size))
     out_ep.write(b'\x00' * 0xC)
 
-def file_range_cmd(nsp_dir, in_ep, out_ep, data_size):
+def file_range_cmd(nsp_dir, in_ep, out_ep, data_size, padding=False):
     file_range_header = in_ep.read(0x20)
 
     range_size = struct.unpack('<Q', file_range_header[:8])[0]
@@ -54,20 +58,27 @@ def file_range_cmd(nsp_dir, in_ep, out_ep, data_size):
     nsp_name = bytes(in_ep.read(nsp_name_len)).decode('utf-8')
 
     print('Range Size: {}, Range Offset: {}, Name len: {}, Name: {}'.format(range_size, range_offset, nsp_name_len, nsp_name))
-    send_response_header(out_ep, CMD_ID_FILE_RANGE, range_size)
+    cmd_id = CMD_ID_FILE_RANGE
+    if padding:
+        cmd_id = CMD_ID_FILE_RANGE_PADDED
+    send_response_header(out_ep, cmd_id, range_size)
 
     with open(nsp_name, 'rb') as f:
         f.seek(range_offset)
 
         curr_off = 0x0
         end_off = range_size
-        read_size = 0x100000
+        read_size = BUFFER_SEGMENT_DATA_SIZE
+        if (padding):
+            read_size -= PADDING_SIZE
 
         while curr_off < end_off:
             if curr_off + read_size >= end_off:
                 read_size = end_off - curr_off
 
             buf = f.read(read_size)
+            if (padding):
+                buf = b'\x00' * PADDING_SIZE + buf
             out_ep.write(data=buf, timeout=0)
             curr_off += read_size
 
@@ -91,6 +102,8 @@ def poll_commands(nsp_dir, in_ep, out_ep):
             break
         elif cmd_id == CMD_ID_FILE_RANGE:
             file_range_cmd(nsp_dir, in_ep, out_ep, data_size)
+        elif cmd_id == CMD_ID_FILE_RANGE_PADDED:
+            file_range_cmd(nsp_dir, in_ep, out_ep, data_size, padding=True)
 
 def send_nsp_list(nsp_dir, out_ep):
     nsp_path_list = list()