sys-patch

A script-like system module that patches fs, es, ldr, nifm and nim on boot.

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Config

sys-patch features a simple config. This can be manually edited or updated using the overlay.

The configuration file can be found in /config/sys-patch/config.ini. The file is generated once the module is ran for the first time.

[options]
patch_sysmmc=1   ; 1=(default) patch sysmmc, 0=don't patch sysmmc
patch_emummc=1   ; 1=(default) patch emummc, 0=don't patch emummc
enable_logging=1 ; 1=(default) output /config/sys-patch/log.ini 0=no log
version_skip=1   ; 1=(default) skips out of date patterns, 0=search all patterns

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Overlay

The overlay can be used to change the config options and to see what patches are applied.

• Unpatched means the patch wasn't applied (likely not found).
• Patched (green) means it was patched by sys-patch.
• Patched (yellow) means it was already patched, likely by sigpatches or a custom Atmosphere build.

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Building

prerequisites

• Install devkitpro
• Run the following:

  git clone --recurse-submodules https://github.com/ITotalJustice/sys-patch.git
  cd ./sys-patch
  make

The output of out/ can be copied to your SD card. To activate the sys-module, reboot your switch, or, use sysmodules overlay with the accompanying overlay to activate it.

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What is being patched?

Here's a quick run down of what's being patched:

• fs and es need new patches after every new firmware version.
• ldr needs new patches after every new Atmosphere release.
• nifm ctest patch allows the device to connect to a network without needing to make a connection to a server
• nim patches to the ssl function call within nim that queries "https://api.hac.%.ctest.srv.nintendo.net/v1/time", and crashes the console if console ssl certificate is not intact. This patch instead makes the console not crash.

The patches are applied on boot. Once done, the sys-module stops running. The memory footprint (16kib) and the binary size (~50kib) are both very small.

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FAQ:

If I am using sigpatches already, is there any point in using this?

Yes, in 3 situations.

1. A new ldr patch needs to be created after every Atmosphere update. Sometimes, a new silent Atmosphere update is released. This tool will always patch ldr without having to update patches.

2. Building Atmosphere from src will require you to generate a new ldr patch for that custom built Atmosphere. This is easy enough due to the public scripts / tools that exist out there, however this will always be able to patch ldr.

3. If you forget to update your patches when you update your firmware / Atmosphere, this sys-module should be able to patch everything. So it can be used as a fall back.

Does this mean that I should stop downloading / using sigpatches?

No, I would personally recommend continuing to use sigpatches. Reason being is that should this tool ever break, i likely wont be quick to fix it.

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Credits / Thanks

Software is built on the shoulders of giants. This tool wouldn't be possible without these people:

• MrDude
• BornToHonk (farni)
• TeJay
• ArchBox
• Switchbrew (libnx, switch-examples)
• DevkitPro (toolchain)
• minIni
• libtesla
• Shoutout to the best switch cfw setup guide
• N