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#[cfg(unix)]
extern crate libc;
use std::io::Write;
fn zero_memory(s: &mut String) {
let vec = unsafe { s.as_mut_vec() };
for el in vec.iter_mut() {
*el = 0u8;
}
}
fn fixes_newline(password: &mut String) {
if password.ends_with('\n') {
password.pop();
if password.ends_with('\r') {
password.pop();
}
}
}
pub fn read_password() -> ::std::io::Result<String> {
read_password_with_reader(None::<::std::io::Empty>)
}
#[cfg(unix)]
mod unix {
use libc::{c_int, isatty, tcgetattr, tcsetattr, TCSANOW, ECHO, ECHONL, STDIN_FILENO};
use std::io::{self, BufRead, Write};
use std::os::unix::io::AsRawFd;
fn io_result(ret: c_int) -> ::std::io::Result<()> {
match ret {
0 => Ok(()),
_ => Err(::std::io::Error::last_os_error()),
}
}
pub fn read_password_from_stdin(open_tty: bool) -> ::std::io::Result<String> {
let mut password = String::new();
enum Source {
Tty(io::BufReader<::std::fs::File>),
Stdin(io::Stdin),
}
let (tty_fd, mut source) = if open_tty {
let tty = ::std::fs::File::open("/dev/tty")?;
(tty.as_raw_fd(), Source::Tty(io::BufReader::new(tty)))
} else {
(STDIN_FILENO, Source::Stdin(io::stdin()))
};
let input_is_tty = unsafe { isatty(tty_fd) } == 1;
if input_is_tty {
let mut term = unsafe { ::std::mem::uninitialized() };
let mut term_orig = unsafe { ::std::mem::uninitialized() };
io_result(unsafe { tcgetattr(tty_fd, &mut term) })?;
io_result(unsafe { tcgetattr(tty_fd, &mut term_orig) })?;
term.c_lflag &= !ECHO;
term.c_lflag |= ECHONL;
io_result(unsafe { tcsetattr(tty_fd, TCSANOW, &term) })?;
let input = match source {
Source::Tty(ref mut tty) => tty.read_line(&mut password),
Source::Stdin(ref mut stdin) => stdin.read_line(&mut password),
};
match input {
Ok(_) => {}
Err(err) => {
io_result(unsafe { tcsetattr(tty_fd, TCSANOW, &term_orig) })?;
super::zero_memory(&mut password);
return Err(err);
}
};
match io_result(unsafe { tcsetattr(tty_fd, TCSANOW, &term_orig) }) {
Ok(_) => {}
Err(err) => {
super::zero_memory(&mut password);
return Err(err);
}
}
} else {
let input = match source {
Source::Tty(mut tty) => tty.read_line(&mut password),
Source::Stdin(mut stdin) => stdin.read_line(&mut password),
};
match input {
Ok(_) => {}
Err(err) => {
super::zero_memory(&mut password);
return Err(err);
}
}
}
super::fixes_newline(&mut password);
Ok(password)
}
pub fn display_on_tty(prompt: &str) -> ::std::io::Result<()> {
let mut stream =
::std::fs::OpenOptions::new().write(true).open("/dev/tty")?;
write!(stream, "{}", prompt)?;
stream.flush()
}
}
#[cfg(windows)]
mod windows {
extern crate winapi;
extern crate kernel32;
use std::io::{self, BufRead, Write};
use std::os::windows::io::{FromRawHandle, IntoRawHandle};
use self::winapi::winnt::{
GENERIC_READ, GENERIC_WRITE, FILE_SHARE_READ, FILE_SHARE_WRITE,
};
use self::winapi::fileapi::OPEN_EXISTING;
pub fn read_password_from_stdin(open_tty: bool) -> ::std::io::Result<String> {
let mut password = String::new();
let handle = if open_tty {
unsafe {
kernel32::CreateFileA(b"CONIN$\x00".as_ptr() as *const i8,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
::std::ptr::null_mut(), OPEN_EXISTING, 0,
::std::ptr::null_mut())
}
} else {
unsafe {
kernel32::GetStdHandle(winapi::STD_INPUT_HANDLE)
}
};
if handle == winapi::INVALID_HANDLE_VALUE {
return Err(::std::io::Error::last_os_error());
}
let mut mode = 0;
if unsafe { kernel32::GetConsoleMode(handle, &mut mode as winapi::LPDWORD) } == 0 {
return Err(::std::io::Error::last_os_error());
}
let new_mode_flags = winapi::ENABLE_LINE_INPUT | winapi::ENABLE_PROCESSED_INPUT;
if unsafe { kernel32::SetConsoleMode(handle, new_mode_flags) } == 0 {
return Err(::std::io::Error::last_os_error());
}
let mut source = io::BufReader::new(unsafe {
::std::fs::File::from_raw_handle(handle)
});
let input = source.read_line(&mut password);
let handle = source.into_inner().into_raw_handle();
match input {
Ok(_) => {}
Err(err) => {
super::zero_memory(&mut password);
return Err(err);
}
};
if unsafe { kernel32::SetConsoleMode(handle, mode) } == 0 {
return Err(::std::io::Error::last_os_error());
}
super::fixes_newline(&mut password);
println!("");
Ok(password)
}
pub fn display_on_tty(prompt: &str) -> ::std::io::Result<()> {
let handle = unsafe {
kernel32::CreateFileA(b"CONOUT$\x00".as_ptr() as *const i8,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
::std::ptr::null_mut(), OPEN_EXISTING, 0,
::std::ptr::null_mut())
};
if handle == winapi::INVALID_HANDLE_VALUE {
return Err(::std::io::Error::last_os_error());
}
let mut stream = unsafe {
::std::fs::File::from_raw_handle(handle)
};
write!(stream, "{}", prompt)?;
stream.flush()
}
}
#[cfg(unix)]
use unix::{read_password_from_stdin, display_on_tty};
#[cfg(windows)]
use windows::{read_password_from_stdin, display_on_tty};
pub fn read_password_with_reader<T>(source: Option<T>) -> ::std::io::Result<String>
where T: ::std::io::BufRead {
match source {
Some(mut reader) => {
let mut password = String::new();
if let Err(err) = reader.read_line(&mut password) {
zero_memory(&mut password);
Err(err)
} else {
fixes_newline(&mut password);
Ok(password)
}
},
None => read_password_from_stdin(false),
}
}
pub fn read_password_from_tty(prompt: Option<&str>)
-> ::std::io::Result<String> {
if let Some(prompt) = prompt {
display_on_tty(prompt)?;
}
read_password_from_stdin(true)
}
pub fn prompt_password_stdout(prompt: &str) -> std::io::Result<String> {
let mut stdout = std::io::stdout();
write!(stdout, "{}", prompt)?;
stdout.flush()?;
read_password()
}
pub fn prompt_password_stderr(prompt: &str) -> std::io::Result<String> {
let mut stderr = std::io::stderr();
write!(stderr, "{}", prompt)?;
stderr.flush()?;
read_password()
}
#[cfg(test)]
mod tests {
use std::io::Cursor;
fn mock_input_crlf() -> Cursor<&'static [u8]> {
Cursor::new(&b"A mocked response.\r\n"[..])
}
fn mock_input_lf() -> Cursor<&'static [u8]> {
Cursor::new(&b"A mocked response.\n"[..])
}
#[test]
fn can_read_from_redirected_input() {
let response = ::read_password_with_reader(Some(mock_input_crlf())).unwrap();
assert_eq!(response, "A mocked response.");
let response = ::read_password_with_reader(Some(mock_input_lf())).unwrap();
assert_eq!(response, "A mocked response.");
}
}