Update

CMakeLists.txt

@@ -6,7 +6,14 @@ file(GLOB_RECURSE HEADERS "include/*.h")
 
 #TODO more architectures.
 if (UNIX AND NOT APPLE)
-    file(GLOB_RECURSE SOURCES "src/linux64/*.cpp")
+    if (CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64")
+        file(GLOB_RECURSE SOURCES "src/linux64/*.cpp" "src/linuxCommon/*.cpp")
+    endif()
+
+    if (CMAKE_SYSTEM_PROCESSOR MATCHES "riscv64")
+        file(GLOB_RECURSE SOURCES "src/linuxRV64/*.cpp" "src/linuxCommon/*.cpp")
+    endif()
+
     add_library(FunctionHook SHARED ${SOURCES})
 endif()
 

include/FunctionHook/Hook.h

@@ -1,14 +1,16 @@
 #pragma once
 #include <cstdint>
 #include <type_traits>
+#include <vector>
 
 namespace FunctionHooking {
     class Detour {
     private:
         void* source = nullptr; //The function to be hooked.
         void* destination = nullptr; //The function we are redirecting execution to.
-        uint8_t overwritten_bytes[13] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
+
-        uint8_t hook_bytes[13] = {0x49, 0xBA, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x41, 0xFF, 0xE2};
+        std::vector<uint8_t> overwritten_bytes{};
+        std::vector<uint8_t> hook_bytes{};
         void createHook(void* source_address, void* destination_address);
     public:
         void removeHook();

src/linux64/Hook.cpp

@@ -7,8 +7,11 @@ void FunctionHooking::Detour::createHook(void* source_address, void* destination
     source = source_address;
     destination = destination_address;
 
+    hook_bytes.insert(hook_bytes.begin(), {0x49, 0xBA, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,0x41, 0xFF, 0xE2});
+    overwritten_bytes.resize(hook_bytes.size());
+
     //Save the bytes to be overwritten from the function prelude.
-    memcpy(&overwritten_bytes, source_address, 13);
+    memcpy(overwritten_bytes.data(), source_address, hook_bytes.size());
 
     //Put the destination address into the jump.
     memcpy(&hook_bytes[2], &destination_address, sizeof(void*));
@@ -17,24 +20,8 @@ void FunctionHooking::Detour::createHook(void* source_address, void* destination
     mprotect((void*)((uintptr_t)source_address & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_WRITE|PROT_EXEC);
 
     //Write the jmp to the beginning of the function prelude.
-    memcpy(source_address, hook_bytes, sizeof(hook_bytes));
+    memcpy(source_address, hook_bytes.data(), hook_bytes.size());
 
     //Make the memory page non-writable again.
     mprotect((void*)((uintptr_t)source_address & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_EXEC);
-}
+}
-
-void FunctionHooking::Detour::removeHook() {
-
-    //Make the target memory page writable.
-    mprotect((void*)((uintptr_t)source & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_WRITE|PROT_EXEC);
-
-    //Replace our hook with the bytes that were originally there.
-    memcpy(source, &overwritten_bytes, 13);
-
-    //Make the memory page non-writable again.
-    mprotect((void*)((uintptr_t)source & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_EXEC);
-}
-
-FunctionHooking::Detour::Detour(void *source_address, void *destination_address) {
-    createHook(source_address, destination_address);
-}

src/linuxCommon/Hook.cpp

@@ -0,0 +1,20 @@
+#include <FunctionHook/Hook.h>
+#include <sys/mman.h>
+#include <csignal>
+#include <cstring>
+
+void FunctionHooking::Detour::removeHook() {
+
+    //Make the target memory page writable.
+    mprotect((void*)((uintptr_t)source & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_WRITE|PROT_EXEC);
+
+    //Replace our hook with the bytes that were originally there.
+    memcpy(source, overwritten_bytes.data(), overwritten_bytes.size());
+
+    //Make the memory page non-writable again.
+    mprotect((void*)((uintptr_t)source & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_EXEC);
+}
+
+FunctionHooking::Detour::Detour(void *source_address, void *destination_address) {
+    createHook(source_address, destination_address);
+}

src/linuxRV64/Hook.cpp

@@ -0,0 +1,40 @@
+#include <FunctionHook/Hook.h>
+#include <sys/mman.h>
+#include <csignal>
+#include <cstring>
+
+void FunctionHooking::Detour::createHook(void* source_address, void* destination_address) {
+    source = source_address;
+    destination = destination_address;
+
+    hook_bytes.insert(hook_bytes.begin(), { 0x17, 0x05, 0x00, 0x00, 0x03, 0x25, 0x05, 0x00, 0x67, 0x00, 0x0a, 0x00} );
+
+    overwritten_bytes.resize(hook_bytes.size() + 8);
+
+    //Save the bytes to be overwritten from the function prelude
+    memcpy(overwritten_bytes.data(), source_address, hook_bytes.size());
+
+    //Calculate the offset.
+    intptr_t offset = (intptr_t)destination_address - (intptr_t)source_address;
+
+    //Place the offset into the auipc instruction
+    memcpy(&hook_bytes[1], &offset, sizeof(uint32_t));
+
+    //Append the destination address after the instructions
+    hook_bytes.insert(hook_bytes.end(), (uint8_t*)&destination_address, (uint8_t*)&destination_address + sizeof(void*));
+
+    //Save the bytes to be overwritten from the function prelude.
+    memcpy(overwritten_bytes.data(), source_address, hook_bytes.size());
+
+    //Put the destination address into the jump.
+    memcpy(&hook_bytes[2], &destination_address, sizeof(void*));
+
+    //Make the target memory page writable.
+    mprotect((void*)((uintptr_t)source_address & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_WRITE|PROT_EXEC);
+
+    //Write the jmp to the beginning of the function prelude.
+    memcpy(source_address, hook_bytes.data(), hook_bytes.size());
+
+    //Make the memory page non-writable again.
+    mprotect((void*)((uintptr_t)source_address & ~(sysconf(_SC_PAGE_SIZE)-1)), sysconf(_SC_PAGE_SIZE), PROT_READ|PROT_EXEC);
+}