A Linux->Lilium Compatibility layer (like Wine).
The primary component of winter-lily is a custom ELF Loader, wl-ld-lilium.so. This behaves like ld-lilium.so but can also load native (Linux) shared libraries.
On top of the standard Lilium rtld interface, it exposes the following additional symbols:
__wl_rtld_open_native(used bykmgmt:OpenKModule).
Note that both lillum and native libraries cannot have any PF_W | PF_X segments (PT_LOAD or PT_GNU_STACK). Also, regardless of PT_GNU_STACK, the stack will never be executable when mapped.
Due to limitations in the implementation, Lilium currently does not handle relocating read-only segments. This includes textrel and relro. This will be fixed in the future. However, it does support both eager and lazy plt binding.
The wl-native-subsys (a22304af-3619-59d8-9a95-1335d8e45441) extension subsystem is loaded by default in every program ran by winter-lily. It does not have a fixed subsystem number and must be queried by using its subsystem ID for a SysInfoRequestAvailableSubsystem to determine the subsystem number, version, and supported syscalls.
The wl-native-subsys extension allows managing winter-lily, and executing Linux native code. It is only available on winter-lily, and no attempts to emulate it on Lilium itself will be made.
See the knum description for the system calls exposed by wl-native-subsys. The system calls are also available by name in a dynamically linked program.
The Implementation of Lilium is not complete. It is designed to be mostly compatible with the kernel and default USI and execute most programs. However, a few limitations are placed on programs supported
winter-lily does not attempt to emulate Lilium's permission system, instead relying on Linux's far less granular (and far more limited) permission system.
As a consequence, the security operations (in the base subsystem) are not reliable. Operations that modify a security context are no-ops currently, and operations for testing permissions do not necessarily return any particular value.
This may change in the future, or may be moved into a separate project, using controls like