minecraft-pi-reborn/runtime
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This commit is contained in:
TheBrokenRail 2024-06-08 03:09:44 -04:00
parent b2cf446e9d
commit 027e58ee9b
7 changed files with 66 additions and 44 deletions
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16
include/trampoline/types.h
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@ -2,25 +2,19 @@
#include <stdint.h>
// Switch Between Pipe?PTrace Mode
#ifdef MCPI_USE_NATIVE_TRAMPOLINE
#define TRAMPOLINE_USE_PTRACE_ENV "_MCPI_TRAMPOLINE_USE_PTRACE"
#endif
// Shared Memory
#define TRAMPOLINE_SHARED_MEMORY_ENV "_MCPI_TRAMPOLINE_SHARED_MEMORY"
// Switch Between Pipe/PTrace Mode
#define TRAMPOLINE_USE_PIPES_ENV "_MCPI_TRAMPOLINE_USE_PIPES"
// System Call Constants
#define MAX_TRAMPOLINE_ARGS_SIZE 2097152 // 2 MiB
#define TRAMPOLINE_SYSCALL 0x1337
// Pipe Constants
#ifdef MCPI_USE_NATIVE_TRAMPOLINE
#define TRAMPOLINE_ARGUMENTS_PIPE_ENV "_MCPI_TRAMPOLINE_ARGUMENTS"
#define TRAMPOLINE_RETURN_VALUE_PIPE_ENV "_MCPI_TRAMPOLINE_RETURN_VALUE"
struct trampoline_pipe_arguments {
uint32_t id;
uint32_t length;
uint32_t args_addr;
};
#endif
// Function Types
typedef void (*trampoline_writer_t)(uint32_t guest_addr, void *data, uint32_t size);

2
native/CMakeLists.txt
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@ -15,7 +15,7 @@ add_executable(trampoline
target_compile_options(trampoline PRIVATE -Wall -Wextra -Werror -Wpointer-arith -Wshadow -Wnull-dereference)
# Link
target_link_libraries(trampoline dl trampoline-headers)
target_link_libraries(trampoline dl rt trampoline-headers)
# RPath
set_target_properties(trampoline PROPERTIES INSTALL_RPATH "$ORIGIN/../lib/native")

5
native/src/main.cpp
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@ -16,8 +16,9 @@ int main(__attribute__((unused)) int argc, char *argv[]) {
if (argc < 2) {
ERR("Invalid Arguments");
}
bool use_ptrace = getenv(TRAMPOLINE_USE_PTRACE_ENV) != nullptr;
bool use_ptrace = getenv(TRAMPOLINE_USE_PIPES_ENV) == nullptr;
// Setup
init_shared_memory_common();
if (!use_ptrace) {
init_pipe_common();
}
@ -28,6 +29,7 @@ int main(__attribute__((unused)) int argc, char *argv[]) {
} else if (pid == 0) {
// Setup
setpgid(0, 0);
init_shared_memory_guest();
if (use_ptrace) {
init_ptrace_guest();
} else {
@ -40,6 +42,7 @@ int main(__attribute__((unused)) int argc, char *argv[]) {
// Parent
// Setup Trampoline
init_shared_memory_host();
init_signals(pid);
init_memory(pid);
init_trampoline();

56
native/src/memory.cpp
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@ -1,18 +1,22 @@
#include <sys/uio.h>
#include <cstring>
#include <cerrno>
#include <sys/mman.h>
#include <fcntl.h>
#include <string>
#include <unistd.h>
#include <trampoline/types.h>
#include "memory.h"
#include "log.h"
// Store PID
// Read Memory
static pid_t guest_pid;
void init_memory(pid_t pid) {
guest_pid = pid;
}
// Read Memory
void memory_reader(uint32_t guest_addr, void *data, uint32_t size) {
void memory_writer(uint32_t guest_addr, void *data, uint32_t size) {
if (size == 0) {
return;
}
@ -22,22 +26,36 @@ void memory_reader(uint32_t guest_addr, void *data, uint32_t size) {
iovec remote[1];
remote[0].iov_base = (void *) (uint64_t) guest_addr;
remote[0].iov_len = size;
ssize_t ret = process_vm_readv(guest_pid, local, 1, remote, 1, 0);
if (ret != size) {
ERR("Unable To Read Data: %s", strerror(errno));
}
}
// Write Memory
void memory_writer(uint32_t guest_addr, void *data, uint32_t size) {
iovec local[1];
local[0].iov_base = data;
local[0].iov_len = size;
iovec remote[1];
remote[0].iov_base = (void *) (uint64_t) guest_addr;
remote[0].iov_len = size;
ssize_t ret = process_vm_writev(guest_pid, local, 1, remote, 1, 0);
const ssize_t ret = process_vm_writev(guest_pid, local, 1, remote, 1, 0);
if (ret != size) {
ERR("Unable To Write Data: %s", strerror(errno));
}
}
// Shared Memory
static std::string shared_memory_name;
static int shared_memory_fd;
void init_shared_memory_common() {
shared_memory_name = std::string("/mcpi-trampoline-") + std::to_string(getpid());
shared_memory_fd = shm_open(shared_memory_name.c_str(), O_CREAT | O_EXCL | O_RDWR, 0600);
if (shared_memory_fd == -1) {
ERR("Unable To Create Shared Memory: %s", strerror(errno));
}
if (ftruncate(shared_memory_fd, MAX_TRAMPOLINE_ARGS_SIZE) == -1) {
ERR("Unable To Set Shared Memory Size: %s", strerror(errno));
}
}
void init_shared_memory_guest() {
setenv(TRAMPOLINE_SHARED_MEMORY_ENV, shared_memory_name.c_str(), true);
}
unsigned char *shared_memory_host_only;
void init_shared_memory_host() {
shared_memory_host_only = (unsigned char *) mmap(nullptr, MAX_TRAMPOLINE_ARGS_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, shared_memory_fd, 0);
if (shared_memory_host_only == MAP_FAILED) {
ERR("Unable To Map Shared Memory: %s", strerror(errno));
}
}
void free_shared_memory() {
munmap(shared_memory_host_only, MAX_TRAMPOLINE_ARGS_SIZE);
shm_unlink(shared_memory_name.c_str());
}

9
native/src/memory.h
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@ -3,6 +3,13 @@
#include <cstdint>
#include <sys/types.h>
void memory_reader(uint32_t guest_addr, void *data, uint32_t size);
// Read External Memory
void memory_writer(uint32_t guest_addr, void *data, uint32_t size);
void init_memory(pid_t guest_pid);
// Shared Memory
void init_shared_memory_common();
void init_shared_memory_guest();
void init_shared_memory_host();
extern unsigned char *shared_memory_host_only;
void free_shared_memory();

11
native/src/pipe/pipe.cpp
View File

@ -44,11 +44,9 @@ void init_pipe_host(pid_t guest_pid) {
close(arguments_pipe[PIPE_WRITE]);
close(return_value_pipe[PIPE_READ]);
// Wait For Commands
trampoline_pipe_arguments cmd = {};
while (read(arguments_pipe[PIPE_READ], &cmd, sizeof(trampoline_pipe_arguments)) > 0) {
static unsigned char args[MAX_TRAMPOLINE_ARGS_SIZE];
memory_reader(cmd.args_addr, args, cmd.length);
uint32_t ret = trampoline(cmd.id, args);
uint32_t cmd;
while (read(arguments_pipe[PIPE_READ], &cmd, sizeof(uint32_t)) > 0) {
uint32_t ret = trampoline(cmd, shared_memory_host_only);
write(return_value_pipe[PIPE_WRITE], &ret, sizeof(uint32_t));
}
// Reap Child
@ -56,6 +54,9 @@ void init_pipe_host(pid_t guest_pid) {
if (waitpid(guest_pid, &status, 0) == -1) {
ERR("Unable To Reap Child: %s", strerror(errno));
}
// Close Shared Memory
free_shared_memory();
// Exit
if (WIFEXITED(status)) {
exit(WEXITSTATUS(status));
} else {

9
native/src/ptrace/loop.cpp
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@ -7,7 +7,6 @@
#ifndef __aarch64__
#error "Unsupported Host Architecture"
#endif
#include <asm/ptrace.h>
#include "ptrace.h"
#include "../log.h"
@ -27,6 +26,7 @@ void safe_wait(pid_t guest_pid, int *status) {
}
if (WIFEXITED(real_status)) {
// Process Exited
free_shared_memory();
exit(WEXITSTATUS(real_status));
}
if (status != nullptr) {
@ -92,6 +92,7 @@ static void set_syscall_return(pid_t guest_pid, arm32_pt_regs *regs) {
// Main Loop
void loop_ptrace(pid_t guest_pid) {
unsigned char *args = shared_memory_host_only;
while (true) {
// Wait For Syscall
ptrace_wait_syscall(guest_pid);
@ -105,11 +106,9 @@ void loop_ptrace(pid_t guest_pid) {
uint32_t length;
uint32_t args_addr;
get_arguments(&regs, &id, &length, &args_addr);
static unsigned char args[MAX_TRAMPOLINE_ARGS_SIZE];
memory_reader(args_addr, args, length);
// Run Trampoline
uint32_t ret = trampoline(id, args);
memory_writer(args_addr, &ret, sizeof(uint32_t));
const uint32_t ret = trampoline(id, args);
*(uint32_t *) args = ret;
// Set Syscall Return
set_syscall_return(guest_pid, &regs);
}