Modifed debug target type representation

This commit is contained in:
Elnath 2025-05-18 15:17:47 +02:00
parent aa661db532
commit 88072597a1
2 changed files with 50 additions and 52 deletions

View File

@ -1,8 +1,8 @@
use crate::syscall_info::{syscall_info, SyscallInfo, SyscallInfoError};
use either::{Either, Left, Right}; use either::{Either, Left, Right};
use nix::libc::user_regs_struct; use nix::libc::user_regs_struct;
use nix::sys::wait::{waitid, Id, WaitPidFlag, WaitStatus}; use nix::sys::wait::{waitid, Id, WaitPidFlag, WaitStatus};
use nix::unistd::Pid; use nix::unistd::Pid;
use crate::syscall_info::{SyscallInfo, SyscallInfoError, syscall_info};
#[derive(thiserror::Error, Debug)] #[derive(thiserror::Error, Debug)]
#[error("Error when calling ptrace: {0}")] #[error("Error when calling ptrace: {0}")]
@ -24,85 +24,82 @@ pub enum DebugError {
UnexpectedWaitStatus(nix::sys::wait::WaitStatus), UnexpectedWaitStatus(nix::sys::wait::WaitStatus),
} }
pub struct DebugTarget<S: DebugState> { pub struct StoppedTarget {
state: S, pub pid: Pid,
} }
pub trait DebugState {
#[allow(dead_code)]
fn pid(&self) -> Pid;
}
pub struct Stopped {
pid: Pid,
}
impl DebugState for Stopped {
fn pid(&self) -> Pid { self.pid }
}
#[allow(dead_code)] #[allow(dead_code)]
impl DebugTarget<Stopped> { impl StoppedTarget {
fn to_running(self) -> RunningTarget {
RunningTarget { pid: self.pid }
}
pub fn new(pid: Pid) -> Result<Self, DebugError> { pub fn new(pid: Pid) -> Result<Self, DebugError> {
waitid(Id::Pid(pid), WaitPidFlag::WSTOPPED).map_err(WaitError)?; waitid(Id::Pid(pid), WaitPidFlag::WSTOPPED).map_err(WaitError)?;
// Needed for waiting on syscalls and apparently also for getting syscall info (can not get it to work without this) // Needed for waiting on syscalls and apparently also for getting syscall info (can not get it to work without this)
nix::sys::ptrace::setoptions(pid, nix::sys::ptrace::Options::PTRACE_O_TRACESYSGOOD).map_err(PTraceError)?; nix::sys::ptrace::setoptions(pid, nix::sys::ptrace::Options::PTRACE_O_TRACESYSGOOD).map_err(PTraceError)?;
Ok(DebugTarget { state: Stopped { pid } }) Ok(Self { pid })
} }
pub fn cont(self) -> Result<DebugTarget<Running>, PTraceError> { pub fn cont(self) -> Result<RunningTarget, PTraceError> {
nix::sys::ptrace::cont(self.state.pid, None).map_err(PTraceError)?; nix::sys::ptrace::cont(self.pid, None).map_err(PTraceError)?;
Ok(DebugTarget { state: Running { pid: self.state.pid } }) Ok(self.to_running())
} }
pub fn stepi(self) -> Result<DebugTarget<Running>, PTraceError> { pub fn stepi(self) -> Result<RunningTarget, PTraceError> {
nix::sys::ptrace::step(self.state.pid, None).map_err(PTraceError)?; nix::sys::ptrace::step(self.pid, None).map_err(PTraceError)?;
Ok(DebugTarget { state: Running { pid: self.state.pid } }) Ok(self.to_running())
} }
pub fn cont_syscall(self) -> Result<DebugTarget<Running>, PTraceError> { pub fn cont_syscall(self) -> Result<RunningTarget, PTraceError> {
nix::sys::ptrace::syscall(self.state.pid, None).map_err(PTraceError)?; nix::sys::ptrace::syscall(self.pid, None).map_err(PTraceError)?;
Ok(DebugTarget { state: Running { pid: self.state.pid } }) Ok(self.to_running())
} }
pub fn get_registers(&self) -> Result<user_regs_struct, PTraceError> { pub fn get_registers(&self) -> Result<user_regs_struct, PTraceError> {
Ok(nix::sys::ptrace::getregs(self.state.pid)?) Ok(nix::sys::ptrace::getregs(self.pid)?)
} }
pub fn get_syscall_info(&self) -> Result<SyscallInfo, SyscallInfoError> { pub fn get_syscall_info(&self) -> Result<SyscallInfo, SyscallInfoError> {
Ok(syscall_info(self.state.pid.as_raw())?) Ok(syscall_info(self.pid.as_raw())?)
} }
} }
pub struct Running { pub struct RunningTarget {
pid: Pid, pub pid: Pid,
}
impl DebugState for Running {
fn pid(&self) -> Pid { self.pid }
} }
#[allow(dead_code)] #[allow(dead_code)]
impl DebugTarget<Running> { impl RunningTarget {
pub fn wait_for_something(self) -> Result<Either<DebugTarget<Stopped>, i32>, DebugError> { fn to_stopped(self) -> StoppedTarget {
match waitid(Id::Pid(self.state.pid), WaitPidFlag::WSTOPPED | WaitPidFlag::WEXITED).map_err(WaitError)? { StoppedTarget { pid: self.pid }
WaitStatus::Exited(_pid, exit_code) => Ok(Right(exit_code)), }
WaitStatus::PtraceEvent(..) | WaitStatus::PtraceSyscall(..) => Ok(Left(DebugTarget { state: Stopped { pid: self.state.pid } })),
pub fn wait_for_something(self) -> Result<Either<StoppedTarget, ExitedTarget>, DebugError> {
match waitid(Id::Pid(self.pid), WaitPidFlag::WSTOPPED | WaitPidFlag::WEXITED).map_err(WaitError)? {
WaitStatus::Exited(_pid, exit_code) => Ok(Right(ExitedTarget { exit_code, was_pid: self.pid })),
WaitStatus::PtraceEvent(..) | WaitStatus::PtraceSyscall(..) => Ok(Left(self.to_stopped())),
status => Err(DebugError::UnexpectedWaitStatus(status)), status => Err(DebugError::UnexpectedWaitStatus(status)),
} }
} }
pub fn wait_for_syscall(self) -> Result<DebugTarget<Stopped>, DebugError> { pub fn wait_for_syscall(self) -> Result<StoppedTarget, DebugError> {
match waitid(Id::Pid(self.state.pid), WaitPidFlag::WSTOPPED).map_err(WaitError)? { match waitid(Id::Pid(self.pid), WaitPidFlag::WSTOPPED).map_err(WaitError)? {
WaitStatus::PtraceSyscall(..) => Ok(DebugTarget { state: Stopped { pid: self.state.pid } }), WaitStatus::PtraceSyscall(..) => Ok(self.to_stopped()),
status => Err(DebugError::UnexpectedWaitStatus(status)), status => Err(DebugError::UnexpectedWaitStatus(status)),
} }
} }
pub fn wait_for_exit(self) -> Result<i32, DebugError> { pub fn wait_for_exit(self) -> Result<ExitedTarget, DebugError> {
match waitid(Id::Pid(self.state.pid), WaitPidFlag::WEXITED).map_err(WaitError)? { match waitid(Id::Pid(self.pid), WaitPidFlag::WEXITED).map_err(WaitError)? {
WaitStatus::Exited(_pid, exit_code) => Ok(exit_code), WaitStatus::Exited(_pid, exit_code) => Ok(ExitedTarget { exit_code, was_pid: self.pid }),
status => Err(DebugError::UnexpectedWaitStatus(status)) status => Err(DebugError::UnexpectedWaitStatus(status))
} }
} }
} }
pub struct ExitedTarget {
pub exit_code: i32,
pub was_pid: Pid,
}

View File

@ -3,7 +3,7 @@ mod debug_target;
mod syscall_info; mod syscall_info;
mod syscall_names; mod syscall_names;
use crate::debug_target::{DebugTarget, Stopped}; use crate::debug_target::{ExitedTarget, StoppedTarget};
use color_eyre::eyre::eyre; use color_eyre::eyre::eyre;
use either::Either; use either::Either;
use nix::libc::user_regs_struct; use nix::libc::user_regs_struct;
@ -14,7 +14,7 @@ use nix::unistd::{fork, ForkResult, Pid};
use std::ffi::{c_long, c_void, CString}; use std::ffi::{c_long, c_void, CString};
#[allow(dead_code)] #[allow(dead_code)]
fn single_step_all(mut target: DebugTarget<Stopped>) -> color_eyre::Result<()> { fn single_step_all(mut target: StoppedTarget) -> color_eyre::Result<()> {
let mut instruction_number = 0; let mut instruction_number = 0;
loop { loop {
instruction_number += 1; instruction_number += 1;
@ -22,7 +22,7 @@ fn single_step_all(mut target: DebugTarget<Stopped>) -> color_eyre::Result<()> {
println!("🔎 [==> {}] rip= {:#016x}, rax = 0x{rax:x} ({rax})", instruction_number, regs.rip, rax = regs.rax); println!("🔎 [==> {}] rip= {:#016x}, rax = 0x{rax:x} ({rax})", instruction_number, regs.rip, rax = regs.rax);
match target.stepi()?.wait_for_something()? { match target.stepi()?.wait_for_something()? {
Either::Left(t) => target = t, Either::Left(t) => target = t,
Either::Right(exit_code) => { Either::Right(ExitedTarget { exit_code, was_pid: _was_pid }) => {
println!("👋 Child exited with code {exit_code}"); println!("👋 Child exited with code {exit_code}");
return Ok(()); return Ok(());
} }
@ -31,14 +31,14 @@ fn single_step_all(mut target: DebugTarget<Stopped>) -> color_eyre::Result<()> {
} }
#[allow(dead_code)] #[allow(dead_code)]
fn strace(mut target: DebugTarget<Stopped>) -> color_eyre::Result<()> { fn strace(mut target: StoppedTarget) -> color_eyre::Result<()> {
loop { loop {
match target.cont_syscall()?.wait_for_something()? { match target.cont_syscall()?.wait_for_something()? {
Either::Left(t) => { Either::Left(t) => {
println!("{:?}", t.get_syscall_info()); println!("{:?}", t.get_syscall_info());
target = t; target = t;
} }
Either::Right(exit_code) => { Either::Right(ExitedTarget { exit_code, was_pid: _was_pid }) => {
println!("👋 Child exited with code {exit_code}"); println!("👋 Child exited with code {exit_code}");
return Ok(()); return Ok(());
} }
@ -100,16 +100,17 @@ fn breakpoint_fun(child_pid: Pid) -> color_eyre::Result<()> {
fn main() -> color_eyre::Result<()> { fn main() -> color_eyre::Result<()> {
color_eyre::install()?; color_eyre::install()?;
let child_exec_path = CString::new(env!("C_PROG_PATH"))?; let child_exec_path = CString::new(env!("ASM_PROG_PATH"))?;
match unsafe { fork() } { match unsafe { fork() } {
Ok(ForkResult::Child) => child::starti(child_exec_path), Ok(ForkResult::Child) => child::starti(child_exec_path),
Ok(ForkResult::Parent { child: child_pid }) => { Ok(ForkResult::Parent { child: child_pid }) => {
println!("✔️ Created child {child_pid}"); println!("✔️ Created child {child_pid}");
let target = DebugTarget::new(child_pid)?; let target = StoppedTarget::new(child_pid)?;
println!("✔️ Child ready!"); println!("✔️ Child ready!");
// println!("🔎 rip: {:#x}", target.get_registers()?.rip); // println!("🔎 rip: {:#x}", target.get_registers()?.rip);
// //
// //