通过以下示例，我一直在研究延迟加载（delayimp）管道作为 Windows 上缺少的 RPATH 功能的可能后端：
#include <stdio.h>
int __declspec(dllimport) foo(int arg);
int main(int argc, char* argv[])
{
printf("foo() = %d\n", foo(foo(argc)));
return 0;
}
GNU 和 LLVM 都使用“dlltool”类似地实现延迟加载（然而，LLVM 的 dlltool 似乎已合并到“ld-link”中）。本质上，在 LLVMlld/COFF/DLL.cpp或 BinUtil中执行的任务dlltool.c有两个：
- 为延迟加载函数生成跳转表存根（参见下面的示例）
- 生成应部署 __delayLoadHelper2 代码的蹦床（请参见下面的示例）
成功绑定后， __delayLoadHelper2似乎将解析的函数地址直接写入可执行代码部分：
extern "C"
FARPROC WINAPI
__delayLoadHelper2(
PCImgDelayDescr pidd,
FARPROC * ppfnIATEntry
) {
...
SetEntryHookBypass:
*ppfnIATEntry = pfnRet; // access violation
...
}
为了对可执行映像进行修改，微软开发了一些花哨的功能，可以临时将写入权限添加到相应的内存区域。
现在的问题是：要修改的代码在进入“.idata”部分的跳转表存根中，并且无法获得写入权限：
if ((Characteristics & IMAGE_SCN_MEM_WRITE) == 0) {
//
// This delay load helper module does not support merging the delay
// load section to a read only section because memory management
// would not guarantee that there is commit available - and thus a
// low memory failure path where the delay load failure hook could
// not be safely invoked (the delay load section would still be
// read only) might be encountered.
//
// It is a build time configuration problem to produce such a
// binary so abort here and now so that the problem can be
// identified & fixed.
//
/* Exception thrown at 0x000000013F3B3F3F in dlltool_test_executable.exe: 0xC0000005: Access violation reading */
__fastfail(FAST_FAIL_DLOAD_PROTECTION_FAILURE);
}
因此，目前硬绑定不起作用，并给出“写访问冲突”。我想知道我在这里缺少哪种二进制配置？
我的测试配置：来自 github 的 LLVM 上游，来自 git 的 BinUtils，MSVC2019，Windows 7。
$ cat trampoline.s
# Import trampoline
.section .text
.global __tailMerge_C__Users_marcusmae_dlltool_build_import_test_lib
__tailMerge_C__Users_marcusmae_dlltool_build_import_test_lib:
pushq %rcx
pushq %rdx
pushq %r8
pushq %r9
subq $40, %rsp
movq %rax, %rdx
leaq __DELAY_IMPORT_DESCRIPTOR_C__Users_marcusmae_dlltool_build_import_test_lib(%rip), %rcx
call __delayLoadHelper2
addq $40, %rsp
popq %r9
popq %r8
popq %rdx
popq %rcx
jmp *%rax
# DELAY_IMPORT_DESCRIPTOR
.section .text$2
.global __DELAY_IMPORT_DESCRIPTOR_C__Users_marcusmae_dlltool_build_import_test_lib
__DELAY_IMPORT_DESCRIPTOR_C__Users_marcusmae_dlltool_build_import_test_lib:
.long 1 # grAttrs
.rva __C__Users_marcusmae_dlltool_build_import_test_lib_iname # rvaDLLName
.rva __DLL_HANDLE_C__Users_marcusmae_dlltool_build_import_test_lib # rvaHmod
.rva __IAT_C__Users_marcusmae_dlltool_build_import_test_lib # rvaIAT
.rva __INT_C__Users_marcusmae_dlltool_build_import_test_lib # rvaINT
.long 0 # rvaBoundIAT
.long 0 # rvaUnloadIAT
.long 0 # dwTimeStamp
.section .data
__DLL_HANDLE_C__Users_marcusmae_dlltool_build_import_test_lib:
.long 0 # Handle
.long 0
#Stuff for compatibility
.section .idata$5
.long 0
.long 0
__IAT_C__Users_marcusmae_dlltool_build_import_test_lib:
.section .idata$4
.long 0
.long 0
.section .idata$4
__INT_C__Users_marcusmae_dlltool_build_import_test_lib:
.section .idata$2
$ objdump -d dorks00000.o
dorks00000.o: file format pe-x86-64
Disassembly of section .text:
0000000000000000 <foo>:
0: ff 25 00 00 00 00 jmpq *0x0(%rip) # 6 <foo+0x6>
6: 48 8d 05 00 00 00 00 lea 0x0(%rip),%rax # d <foo+0xd>
d: e9 00 00 00 00 jmpq 12 <foo+0x12>
...