1 use cfg_if::cfg_if;
2 use crate::errno::Errno;
3 use libc::{self, c_int};
4 use std::ptr;
5 use crate::sys::signal::Signal;
6 use crate::unistd::Pid;
7 use crate::Result;
8
9 pub type RequestType = c_int;
10
11 cfg_if! {
12 if #[cfg(any(target_os = "dragonfly",
13 target_os = "freebsd",
14 target_os = "macos",
15 target_os = "openbsd"))] {
16 #[doc(hidden)]
17 pub type AddressType = *mut ::libc::c_char;
18 } else {
19 #[doc(hidden)]
20 pub type AddressType = *mut ::libc::c_void;
21 }
22 }
23
24 libc_enum! {
25 #[repr(i32)]
26 /// Ptrace Request enum defining the action to be taken.
27 #[non_exhaustive]
28 pub enum Request {
29 PT_TRACE_ME,
30 PT_READ_I,
31 PT_READ_D,
32 #[cfg(target_os = "macos")]
33 PT_READ_U,
34 PT_WRITE_I,
35 PT_WRITE_D,
36 #[cfg(target_os = "macos")]
37 PT_WRITE_U,
38 PT_CONTINUE,
39 PT_KILL,
40 #[cfg(any(any(target_os = "dragonfly",
41 target_os = "freebsd",
42 target_os = "macos"),
43 all(target_os = "openbsd", target_arch = "x86_64"),
44 all(target_os = "netbsd", any(target_arch = "x86_64",
45 target_arch = "powerpc"))))]
46 PT_STEP,
47 PT_ATTACH,
48 PT_DETACH,
49 #[cfg(target_os = "macos")]
50 PT_SIGEXC,
51 #[cfg(target_os = "macos")]
52 PT_THUPDATE,
53 #[cfg(target_os = "macos")]
54 PT_ATTACHEXC
55 }
56 }
57
ptrace_other( request: Request, pid: Pid, addr: AddressType, data: c_int, ) -> Result<c_int>58 unsafe fn ptrace_other(
59 request: Request,
60 pid: Pid,
61 addr: AddressType,
62 data: c_int,
63 ) -> Result<c_int> {
64 Errno::result(libc::ptrace(
65 request as RequestType,
66 libc::pid_t::from(pid),
67 addr,
68 data,
69 )).map(|_| 0)
70 }
71
72 /// Sets the process as traceable, as with `ptrace(PT_TRACEME, ...)`
73 ///
74 /// Indicates that this process is to be traced by its parent.
75 /// This is the only ptrace request to be issued by the tracee.
traceme() -> Result<()>76 pub fn traceme() -> Result<()> {
77 unsafe { ptrace_other(Request::PT_TRACE_ME, Pid::from_raw(0), ptr::null_mut(), 0).map(drop) }
78 }
79
80 /// Attach to a running process, as with `ptrace(PT_ATTACH, ...)`
81 ///
82 /// Attaches to the process specified by `pid`, making it a tracee of the calling process.
attach(pid: Pid) -> Result<()>83 pub fn attach(pid: Pid) -> Result<()> {
84 unsafe { ptrace_other(Request::PT_ATTACH, pid, ptr::null_mut(), 0).map(drop) }
85 }
86
87 /// Detaches the current running process, as with `ptrace(PT_DETACH, ...)`
88 ///
89 /// Detaches from the process specified by `pid` allowing it to run freely, optionally delivering a
90 /// signal specified by `sig`.
detach<T: Into<Option<Signal>>>(pid: Pid, sig: T) -> Result<()>91 pub fn detach<T: Into<Option<Signal>>>(pid: Pid, sig: T) -> Result<()> {
92 let data = match sig.into() {
93 Some(s) => s as c_int,
94 None => 0,
95 };
96 unsafe {
97 ptrace_other(Request::PT_DETACH, pid, ptr::null_mut(), data).map(drop)
98 }
99 }
100
101 /// Restart the stopped tracee process, as with `ptrace(PTRACE_CONT, ...)`
102 ///
103 /// Continues the execution of the process with PID `pid`, optionally
104 /// delivering a signal specified by `sig`.
cont<T: Into<Option<Signal>>>(pid: Pid, sig: T) -> Result<()>105 pub fn cont<T: Into<Option<Signal>>>(pid: Pid, sig: T) -> Result<()> {
106 let data = match sig.into() {
107 Some(s) => s as c_int,
108 None => 0,
109 };
110 unsafe {
111 // Ignore the useless return value
112 ptrace_other(Request::PT_CONTINUE, pid, 1 as AddressType, data).map(drop)
113 }
114 }
115
116 /// Issues a kill request as with `ptrace(PT_KILL, ...)`
117 ///
118 /// This request is equivalent to `ptrace(PT_CONTINUE, ..., SIGKILL);`
kill(pid: Pid) -> Result<()>119 pub fn kill(pid: Pid) -> Result<()> {
120 unsafe {
121 ptrace_other(Request::PT_KILL, pid, 0 as AddressType, 0).map(drop)
122 }
123 }
124
125 /// Move the stopped tracee process forward by a single step as with
126 /// `ptrace(PT_STEP, ...)`
127 ///
128 /// Advances the execution of the process with PID `pid` by a single step optionally delivering a
129 /// signal specified by `sig`.
130 ///
131 /// # Example
132 /// ```rust
133 /// use nix::sys::ptrace::step;
134 /// use nix::unistd::Pid;
135 /// use nix::sys::signal::Signal;
136 /// use nix::sys::wait::*;
137 /// // If a process changes state to the stopped state because of a SIGUSR1
138 /// // signal, this will step the process forward and forward the user
139 /// // signal to the stopped process
140 /// match waitpid(Pid::from_raw(-1), None) {
141 /// Ok(WaitStatus::Stopped(pid, Signal::SIGUSR1)) => {
142 /// let _ = step(pid, Signal::SIGUSR1);
143 /// }
144 /// _ => {},
145 /// }
146 /// ```
147 #[cfg(
148 any(
149 any(target_os = "dragonfly", target_os = "freebsd", target_os = "macos"),
150 all(target_os = "openbsd", target_arch = "x86_64"),
151 all(target_os = "netbsd",
152 any(target_arch = "x86_64", target_arch = "powerpc")
153 )
154 )
155 )]
step<T: Into<Option<Signal>>>(pid: Pid, sig: T) -> Result<()>156 pub fn step<T: Into<Option<Signal>>>(pid: Pid, sig: T) -> Result<()> {
157 let data = match sig.into() {
158 Some(s) => s as c_int,
159 None => 0,
160 };
161 unsafe { ptrace_other(Request::PT_STEP, pid, ptr::null_mut(), data).map(drop) }
162 }
163
164 /// Reads a word from a processes memory at the given address
read(pid: Pid, addr: AddressType) -> Result<c_int>165 pub fn read(pid: Pid, addr: AddressType) -> Result<c_int> {
166 unsafe {
167 // Traditionally there was a difference between reading data or
168 // instruction memory but not in modern systems.
169 ptrace_other(Request::PT_READ_D, pid, addr, 0)
170 }
171 }
172
173 /// Writes a word into the processes memory at the given address
write(pid: Pid, addr: AddressType, data: c_int) -> Result<()>174 pub fn write(pid: Pid, addr: AddressType, data: c_int) -> Result<()> {
175 unsafe { ptrace_other(Request::PT_WRITE_D, pid, addr, data).map(drop) }
176 }
177