95 lines
2.9 KiB
Rust
95 lines
2.9 KiB
Rust
use libc::{c_int, c_char, c_void};
|
|
use std::any::Any;
|
|
use std::cell::UnsafeCell;
|
|
use std::panic::{self, AssertUnwindSafe};
|
|
use std::slice;
|
|
|
|
use error::ErrorStack;
|
|
|
|
/// Wraps a user-supplied callback and a slot for panics thrown inside the callback (while FFI
|
|
/// frames are on the stack).
|
|
///
|
|
/// When dropped, checks if the callback has panicked, and resumes unwinding if so.
|
|
pub struct CallbackState<F> {
|
|
/// The user callback. Taken out of the `Option` when called.
|
|
cb: Option<F>,
|
|
/// If the callback panics, we place the panic object here, to be re-thrown once OpenSSL
|
|
/// returns.
|
|
panic: Option<Box<Any + Send + 'static>>,
|
|
}
|
|
|
|
impl<F> CallbackState<F> {
|
|
pub fn new(callback: F) -> Self {
|
|
CallbackState {
|
|
cb: Some(callback),
|
|
panic: None,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<F> Drop for CallbackState<F> {
|
|
fn drop(&mut self) {
|
|
if let Some(panic) = self.panic.take() {
|
|
panic::resume_unwind(panic);
|
|
}
|
|
}
|
|
}
|
|
|
|
pub unsafe extern fn invoke_passwd_cb_old<F>(buf: *mut c_char,
|
|
size: c_int,
|
|
_rwflag: c_int,
|
|
cb_state: *mut c_void)
|
|
-> c_int
|
|
where F: FnOnce(&mut [c_char]) -> usize
|
|
{
|
|
let callback = &mut *(cb_state as *mut CallbackState<F>);
|
|
|
|
let result = panic::catch_unwind(AssertUnwindSafe(|| {
|
|
let pass_slice = slice::from_raw_parts_mut(buf, size as usize);
|
|
callback.cb.take().unwrap()(pass_slice)
|
|
}));
|
|
|
|
match result {
|
|
Ok(len) => len as c_int,
|
|
Err(err) => {
|
|
callback.panic = Some(err);
|
|
0
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Password callback function, passed to private key loading functions.
|
|
///
|
|
/// `cb_state` is expected to be a pointer to a `CallbackState`.
|
|
pub unsafe extern fn invoke_passwd_cb<F>(buf: *mut c_char,
|
|
size: c_int,
|
|
_rwflag: c_int,
|
|
cb_state: *mut c_void)
|
|
-> c_int
|
|
where F: FnOnce(&mut [u8]) -> Result<usize, ErrorStack>
|
|
{
|
|
let callback = &mut *(cb_state as *mut CallbackState<F>);
|
|
|
|
let result = panic::catch_unwind(AssertUnwindSafe(|| {
|
|
let pass_slice = slice::from_raw_parts_mut(buf as *mut u8, size as usize);
|
|
callback.cb.take().unwrap()(pass_slice)
|
|
}));
|
|
|
|
match result {
|
|
Ok(Ok(len)) => len as c_int,
|
|
Ok(Err(_)) => {
|
|
// FIXME restore error stack
|
|
0
|
|
}
|
|
Err(err) => {
|
|
callback.panic = Some(err);
|
|
0
|
|
}
|
|
}
|
|
}
|
|
|
|
/// This is intended to be used as the inner type for `FooRef` types converted from raw C pointers.
|
|
/// It has an `UnsafeCell` internally to inform the compiler about aliasability and doesn't
|
|
/// implement `Copy`, so it can't be dereferenced.
|
|
pub struct Opaque(UnsafeCell<()>);
|