Files
IChooseYou 67218d3e48 fix: move payload init out of DllMain to avoid loader lock deadlock
RcxPayloadInit() is now an exported function called after LoadLibrary
returns. DllMain only handles cleanup on detach. Timer queue creation
under the loader lock was crashing target processes.
2026-02-22 13:14:01 -07:00

188 lines
5.0 KiB
C++

/*
* test_rpc_host -- loads rcx_payload in-process, acts as the "target".
*
* Usage: test_rpc_host
*
* Prints a READY line (machine-parseable), then waits for the payload
* to shut down (RPC_CMD_SHUTDOWN from the client).
*/
#include "../rcx_rpc_protocol.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>
#ifdef _WIN32
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#else
# include <unistd.h>
# include <dlfcn.h>
# include <fcntl.h>
# include <sys/mman.h>
# include <semaphore.h>
# include <libgen.h>
# include <limits.h>
#endif
/* ── Helpers ──────────────────────────────────────────────────────── */
static uint32_t current_pid()
{
#ifdef _WIN32
return (uint32_t)GetCurrentProcessId();
#else
return (uint32_t)getpid();
#endif
}
static void sleep_ms(int ms)
{
#ifdef _WIN32
Sleep((DWORD)ms);
#else
usleep((useconds_t)ms * 1000);
#endif
}
/* Resolve payload path relative to this executable */
static int payload_path(char* out, int outLen)
{
#ifdef _WIN32
char exePath[MAX_PATH];
GetModuleFileNameA(nullptr, exePath, MAX_PATH);
char* slash = strrchr(exePath, '\\');
if (!slash) slash = strrchr(exePath, '/');
if (slash) *(slash + 1) = '\0';
snprintf(out, outLen, "%srcx_payload.dll", exePath);
#else
char exePath[PATH_MAX];
ssize_t n = readlink("/proc/self/exe", exePath, sizeof(exePath) - 1);
if (n <= 0) return -1;
exePath[n] = '\0';
char* dir = dirname(exePath);
snprintf(out, outLen, "%s/rcx_payload.so", dir);
#endif
return 0;
}
/* Open the main shared memory (read-only, just to monitor payloadReady) */
static void* open_main_shm(uint32_t pid)
{
char shmName[128];
rcx_rpc_shm_name(shmName, sizeof(shmName), pid);
#ifdef _WIN32
HANDLE h = nullptr;
for (int i = 0; i < 500; ++i) {
h = OpenFileMappingA(FILE_MAP_READ, FALSE, shmName);
if (h) break;
sleep_ms(10);
}
if (!h) return nullptr;
void* v = MapViewOfFile(h, FILE_MAP_READ, 0, 0, sizeof(RcxRpcHeader));
return v;
#else
int fd = -1;
for (int i = 0; i < 500; ++i) {
fd = shm_open(shmName, O_RDONLY, 0);
if (fd >= 0) break;
sleep_ms(10);
}
if (fd < 0) return nullptr;
void* v = mmap(nullptr, sizeof(RcxRpcHeader), PROT_READ, MAP_SHARED, fd, 0);
close(fd);
return (v == MAP_FAILED) ? nullptr : v;
#endif
}
/* ── Test buffer (known pattern for client to verify reads/writes) ── */
static uint8_t g_testBuf[65536];
/* ── main ─────────────────────────────────────────────────────────── */
int main(int, char**)
{
uint32_t pid = current_pid();
/* fill test buffer with known pattern */
for (int i = 0; i < (int)sizeof(g_testBuf); ++i)
g_testBuf[i] = (uint8_t)(i & 0xFF);
/* load payload */
char plPath[1024];
if (payload_path(plPath, sizeof(plPath)) != 0) {
fprintf(stderr, "ERROR: cannot determine payload path\n");
return 1;
}
#ifdef _WIN32
HMODULE hPayload = LoadLibraryA(plPath);
if (!hPayload) {
fprintf(stderr, "ERROR: LoadLibrary(%s) failed (%lu)\n",
plPath, GetLastError());
return 1;
}
/* Call RcxPayloadInit() — DllMain is minimal, init must be explicit */
typedef bool (*RcxPayloadInitFn)();
auto pfnInit = (RcxPayloadInitFn)GetProcAddress(hPayload, "RcxPayloadInit");
if (!pfnInit || !pfnInit()) {
fprintf(stderr, "ERROR: RcxPayloadInit() failed or not found\n");
FreeLibrary(hPayload);
return 1;
}
#else
void* hPayload = dlopen(plPath, RTLD_NOW);
if (!hPayload) {
fprintf(stderr, "ERROR: dlopen(%s): %s\n", plPath, dlerror());
return 1;
}
#endif
/* open main shm and wait for payloadReady */
void* shmView = open_main_shm(pid);
if (!shmView) {
fprintf(stderr, "ERROR: failed to open main shared memory\n");
return 1;
}
RcxRpcHeader* hdr = (RcxRpcHeader*)shmView;
for (int i = 0; i < 500; ++i) {
if (hdr->payloadReady) break;
sleep_ms(10);
}
if (!hdr->payloadReady) {
fprintf(stderr, "ERROR: payload did not become ready\n");
return 1;
}
/* print READY line for the client to parse */
printf("READY pid=%u testbuf=0x%llx testlen=%u\n",
pid,
(unsigned long long)(uintptr_t)g_testBuf,
(unsigned)sizeof(g_testBuf));
fflush(stdout);
/* wait until payload shuts down */
while (hdr->payloadReady)
sleep_ms(100);
printf("Payload shut down, exiting.\n");
#ifdef _WIN32
/* give the timer queue a moment to drain */
Sleep(200);
FreeLibrary(hPayload);
if (shmView) UnmapViewOfFile(shmView);
#else
usleep(200000);
dlclose(hPayload);
if (shmView) munmap(shmView, sizeof(RcxRpcHeader));
#endif
return 0;
}