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Wed 29 Apr 2020 03:51:40 PM CEST

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This commit is contained in:
Samuel Tulach
2020-04-29 15:51:40 +02:00
parent 131720686f
commit b216b24b8d
8 changed files with 286 additions and 225 deletions
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68
driver/main.c
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@@ -2,6 +2,8 @@
// instead of SysV ABI, we now have to do transitions
// GNU-EFI has a functionality for this (thanks god)
#define GNU_EFI_USE_MS_ABI 1
#define stdcall __attribute__((stdcall)) // wHy NoT tO jUsT uSe MsVc
#define fastcall __attribute__((fastcall))
// Mandatory defines
#include <efi.h>
@@ -42,11 +44,17 @@ typedef struct _MemoryCommand
{
int magic;
int operation;
unsigned long long data1;
unsigned long long data2;
unsigned long long data[10];
int size;
} MemoryCommand;
// Functions (Windows only)
typedef uintptr_t (stdcall *ExAllocatePool)(int type, uintptr_t size);
typedef void (stdcall *ExFreePool)(uintptr_t address);
typedef void (stdcall *StandardFuncStd)();
typedef void (fastcall *StandardFuncFast)();
typedef unsigned long (stdcall *DriverEntry)(void* driver, void* registry);
// Function that actually performs the r/w
EFI_STATUS
RunCommand(MemoryCommand* cmd)
@@ -62,10 +70,60 @@ RunCommand(MemoryCommand* cmd)
if (cmd->operation == 0)
{
// Same as memcpy function
CopyMem(cmd->data1, cmd->data2, cmd->size);
CopyMem(cmd->data[0], cmd->data[1], cmd->size);
return EFI_SUCCESS;
}
// Call ExAllocatePool
if (cmd->operation == 1)
{
void* function = cmd->data[0]; // Pointer to the function (supplied by client)
ExAllocatePool exalloc = (ExAllocatePool)function;
int temp = cmd->data[1]; // gcc you ok?
uintptr_t allocbase = exalloc(temp, cmd->data[2]);
*(uintptr_t*)cmd->data[3] = allocbase;
}
// Call ExFreePool
if (cmd->operation == 2)
{
void* function = cmd->data[0];
ExFreePool exfree = (ExFreePool)function;
exfree(cmd->data[1]);
}
// Call any void function (__stdcall)
if (cmd->operation == 3)
{
void* function = cmd->data[0];
StandardFuncStd stand = (StandardFuncStd)function;
stand();
}
// Call any void function (__fastcall)
if (cmd->operation == 4)
{
void* function = cmd->data[0];
StandardFuncFast stand = (StandardFuncFast)function;
stand();
}
// Call driver entry
if (cmd->operation == 5)
{
void* function = cmd->data[0];
DriverEntry entry = (DriverEntry)function;
// gcc compiles long as 8 byte
// msvc compiles long as 4 byte
// we are gonna use int
// you can't even imagine how long I was fking
// with this
int status = entry(0, 0);
*(int*)cmd->data[1] = status;
}
// Invalid command
return EFI_UNSUPPORTED;
}
@@ -249,7 +307,7 @@ efi_main(IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable)
TPL_NOTIFY,
SetVirtualAddressMapEvent,
NULL,
VirtualGuid,
&VirtualGuid,
&NotifyEvent);
// Return if event create failed
@@ -264,7 +322,7 @@ efi_main(IN EFI_HANDLE ImageHandle, IN EFI_SYSTEM_TABLE *SystemTable)
TPL_NOTIFY,
ExitBootServicesEvent,
NULL,
ExitGuid,
&ExitGuid,
&ExitEvent);
// Return if event create failed (yet again)