Skip to content

Chain multiple hooks to the same function in a single transaction #10

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
Open

Chain multiple hooks to the same function in a single transaction #10

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
173 changes: 104 additions & 69 deletions Source/SlimDetours/Transaction.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -144,7 +144,7 @@ SlimDetoursTransactionCommit(VOID)
DWORD dwOld;

// Common variables.
PDETOUR_OPERATION o, n;
PDETOUR_OPERATION o, n, m;
PBYTE pbCode;
BOOL freed = FALSE;
ULONG i;
Expand All @@ -159,87 +159,122 @@ SlimDetoursTransactionCommit(VOID)
goto _exit;
}

// Insert or remove each of the detours.
o = s_pPendingOperations;
do
// Insert each of the detours.
for (o = s_pPendingOperations; o != NULL; o = o->pNext)
{
if (o->fIsRemove)
if (!o->fIsAdd)
continue;

DETOUR_TRACE("detours: pbTramp =%p, pbRemain=%p, pbDetour=%p, cbRestore=%u\n",
o->pTrampoline,
o->pTrampoline->pbRemain,
o->pTrampoline->pbDetour,
o->pTrampoline->cbRestore);

DETOUR_TRACE("detours: pbTarget=%p: "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x [before]\n",
o->pbTarget,
o->pbTarget[0], o->pbTarget[1], o->pbTarget[2], o->pbTarget[3],
o->pbTarget[4], o->pbTarget[5], o->pbTarget[6], o->pbTarget[7],
o->pbTarget[8], o->pbTarget[9], o->pbTarget[10], o->pbTarget[11]);

m = NULL;
if (!RtlEqualMemory(o->pbTarget, o->pTrampoline->rbRestore, o->pTrampoline->cbRestore))
{
// Check if the jmps still points where we expect, otherwise someone might have hooked us.
BOOL hookIsStillThere =
#if defined(_X86_) || defined(_AMD64_)
detour_is_jmp_immediate_to(o->pbTarget, o->pTrampoline->rbCodeIn) &&
detour_is_jmp_indirect_to(o->pTrampoline->rbCodeIn, &o->pTrampoline->pbDetour);
#elif defined(_ARM64_)
detour_is_jmp_indirect_to(o->pbTarget, (ULONG64*)&(o->pTrampoline->pbDetour));
#endif
DETOUR_TRACE("detours: target is modified\n");

if (hookIsStillThere)
{
RtlCopyMemory(o->pbTarget, o->pTrampoline->rbRestore, o->pTrampoline->cbRestore);
NtFlushInstructionCache(NtCurrentProcess(), o->pbTarget, o->pTrampoline->cbRestore);
} else
for (n = s_pPendingOperations; n != o; n = n->pNext)
{
// Don't remove in this case, put in bypass mode and leak trampoline.
o->fIsRemove = FALSE;
o->pTrampoline->pbDetour = o->pTrampoline->rbCode;
DETOUR_TRACE("detours: Leaked hook on pbTarget=%p due to external hooking\n", o->pbTarget);
if (n->fIsAdd && n->pbTarget == o->pbTarget)
{
m = n;
}
}
}

*o->ppbPointer = o->pbTarget;
} else if (o->fIsAdd)
if (m != NULL)
{
DETOUR_TRACE("detours: pbTramp =%p, pbRemain=%p, pbDetour=%p, cbRestore=%u\n",
o->pTrampoline,
o->pTrampoline->pbRemain,
o->pTrampoline->pbDetour,
o->pTrampoline->cbRestore);

DETOUR_TRACE("detours: pbTarget=%p: "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x [before]\n",
o->pbTarget,
o->pbTarget[0], o->pbTarget[1], o->pbTarget[2], o->pbTarget[3],
o->pbTarget[4], o->pbTarget[5], o->pbTarget[6], o->pbTarget[7],
o->pbTarget[8], o->pbTarget[9], o->pbTarget[10], o->pbTarget[11]);
DETOUR_TRACE("detours: chaining to last detour in the transaction\n");

#if defined(_X86_) || defined(_AMD64_)
pbCode = detour_gen_jmp_indirect(o->pTrampoline->rbCodeIn, &o->pTrampoline->pbDetour);
NtFlushInstructionCache(NtCurrentProcess(), o->pTrampoline->rbCodeIn, pbCode - o->pTrampoline->rbCodeIn);
pbCode = detour_gen_jmp_immediate(o->pbTarget, o->pTrampoline->rbCodeIn);
pbCode = detour_gen_jmp_indirect(o->pTrampoline->rbCode, &m->pTrampoline->pbDetour);
#elif defined(_ARM64_)
pbCode = detour_gen_jmp_indirect(o->pbTarget, (ULONG64*)&(o->pTrampoline->pbDetour));
pbCode = detour_gen_jmp_indirect(o->pTrampoline->rbCode, (ULONG64*)&(m->pTrampoline->pbDetour));
#endif
pbCode = detour_gen_brk(pbCode, o->pTrampoline->pbRemain);
NtFlushInstructionCache(NtCurrentProcess(), o->pbTarget, pbCode - o->pbTarget);
*o->ppbPointer = o->pTrampoline->rbCode;
UNREFERENCED_PARAMETER(pbCode);

DETOUR_TRACE("detours: pbTarget=%p: "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x [after]\n",
o->pbTarget,
o->pbTarget[0], o->pbTarget[1], o->pbTarget[2], o->pbTarget[3],
o->pbTarget[4], o->pbTarget[5], o->pbTarget[6], o->pbTarget[7],
o->pbTarget[8], o->pbTarget[9], o->pbTarget[10], o->pbTarget[11]);

DETOUR_TRACE("detours: pbTramp =%p: "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x\n",
o->pTrampoline,
o->pTrampoline->rbCode[0], o->pTrampoline->rbCode[1],
o->pTrampoline->rbCode[2], o->pTrampoline->rbCode[3],
o->pTrampoline->rbCode[4], o->pTrampoline->rbCode[5],
o->pTrampoline->rbCode[6], o->pTrampoline->rbCode[7],
o->pTrampoline->rbCode[8], o->pTrampoline->rbCode[9],
o->pTrampoline->rbCode[10], o->pTrampoline->rbCode[11]);
o->pTrampoline->cbCode = 0;

CopyMemory(o->pTrampoline->rbRestore, o->pbTarget, m->pTrampoline->cbRestore);
o->pTrampoline->cbRestore = m->pTrampoline->cbRestore;

RtlZeroMemory(o->pTrampoline->rAlign, sizeof(o->pTrampoline->rAlign));
o->pTrampoline->pbRemain = o->pbTarget + o->pTrampoline->cbRestore;
}

o = o->pNext;
} while (o != NULL);
#if defined(_X86_) || defined(_AMD64_)
pbCode = detour_gen_jmp_indirect(o->pTrampoline->rbCodeIn, &o->pTrampoline->pbDetour);
NtFlushInstructionCache(NtCurrentProcess(), o->pTrampoline->rbCodeIn, pbCode - o->pTrampoline->rbCodeIn);
pbCode = detour_gen_jmp_immediate(o->pbTarget, o->pTrampoline->rbCodeIn);
#elif defined(_ARM64_)
pbCode = detour_gen_jmp_indirect(o->pbTarget, (ULONG64*)&(o->pTrampoline->pbDetour));
#endif
pbCode = detour_gen_brk(pbCode, o->pTrampoline->pbRemain);
NtFlushInstructionCache(NtCurrentProcess(), o->pbTarget, pbCode - o->pbTarget);

*o->ppbPointer = o->pTrampoline->rbCode;

DETOUR_TRACE("detours: pbTarget=%p: "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x [after]\n",
o->pbTarget,
o->pbTarget[0], o->pbTarget[1], o->pbTarget[2], o->pbTarget[3],
o->pbTarget[4], o->pbTarget[5], o->pbTarget[6], o->pbTarget[7],
o->pbTarget[8], o->pbTarget[9], o->pbTarget[10], o->pbTarget[11]);

DETOUR_TRACE("detours: pbTramp =%p: "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x "
"%02x %02x %02x %02x\n",
o->pTrampoline,
o->pTrampoline->rbCode[0], o->pTrampoline->rbCode[1],
o->pTrampoline->rbCode[2], o->pTrampoline->rbCode[3],
o->pTrampoline->rbCode[4], o->pTrampoline->rbCode[5],
o->pTrampoline->rbCode[6], o->pTrampoline->rbCode[7],
o->pTrampoline->rbCode[8], o->pTrampoline->rbCode[9],
o->pTrampoline->rbCode[10], o->pTrampoline->rbCode[11]);
}

// Remove each of the detours.
for (o = s_pPendingOperations; o != NULL; o = o->pNext)
{
if (!o->fIsRemove)
continue;

// Check if the jmps still points where we expect, otherwise someone might have hooked us.
BOOL hookIsStillThere =
#if defined(_X86_) || defined(_AMD64_)
detour_is_jmp_immediate_to(o->pbTarget, o->pTrampoline->rbCodeIn) &&
detour_is_jmp_indirect_to(o->pTrampoline->rbCodeIn, &o->pTrampoline->pbDetour);
#elif defined(_ARM64_)
detour_is_jmp_indirect_to(o->pbTarget, (ULONG64*)&(o->pTrampoline->pbDetour));
#endif

if (hookIsStillThere)
{
RtlCopyMemory(o->pbTarget, o->pTrampoline->rbRestore, o->pTrampoline->cbRestore);
NtFlushInstructionCache(NtCurrentProcess(), o->pbTarget, o->pTrampoline->cbRestore);
} else
{
// Don't remove in this case, put in bypass mode and leak trampoline.
o->fIsRemove = FALSE;
o->pTrampoline->pbDetour = o->pTrampoline->rbCode;
DETOUR_TRACE("detours: Leaked hook on pbTarget=%p due to external hooking\n", o->pbTarget);
}

*o->ppbPointer = o->pbTarget;
}

// Update any suspended threads.
for (i = 0; i < s_ulSuspendedThreadCount; i++)
Expand Down