1 //! Custom error library support for the `openssl` crate.
2 //!
3 //! OpenSSL allows third-party libraries to integrate with its error API. This crate provides a safe interface to that.
4 //!
5 //! # Examples
6 //!
7 //! ```
8 //! use openssl_errors::{openssl_errors, put_error};
9 //! use openssl::error::Error;
10 //!
11 //! // Errors are organized at the top level into "libraries". The
12 //! // openssl_errors! macro can define these.
13 //! //
14 //! // Libraries contain a set of functions and reasons. The library itself,
15 //! // its functions, and its definitions all all have an associated message
16 //! // string. This string is what's shown in OpenSSL errors.
17 //! //
18 //! // The macro creates a type for each library with associated constants for
19 //! // its functions and reasons.
20 //! openssl_errors! {
21 //! pub library MyLib("my cool library") {
22 //! functions {
23 //! FIND_PRIVATE_KEY("find_private_key");
24 //! }
25 //!
26 //! reasons {
27 //! IO_ERROR("IO error");
28 //! BAD_PASSWORD("invalid private key password");
29 //! }
30 //! }
31 //! }
32 //!
33 //! // The put_error! macro pushes errors onto the OpenSSL error stack.
34 //! put_error!(MyLib::FIND_PRIVATE_KEY, MyLib::BAD_PASSWORD);
35 //!
36 //! // Prints `error:80001002:my cool library:find_private_key:invalid private key password:src/lib.rs:27:`
37 //! println!("{}", Error::get().unwrap());
38 //!
39 //! // You can also optionally attach an extra string of context using the
40 //! // standard Rust format syntax.
41 //! let tries = 2;
42 //! put_error!(MyLib::FIND_PRIVATE_KEY, MyLib::IO_ERROR, "tried {} times", tries);
43 //!
44 //! // Prints `error:80001001:my cool library:find_private_key:IO error:src/lib.rs:34:tried 2 times`
45 //! println!("{}", Error::get().unwrap());
46 //! ```
47 #![warn(missing_docs)]
48 #![doc(html_root_url = "https://docs.rs/openssl-errors/0.2")]
49
50 use cfg_if::cfg_if;
51 use libc::{c_char, c_int};
52 use std::borrow::Cow;
53 use std::marker::PhantomData;
54 use std::ptr;
55
56 #[doc(hidden)]
57 pub mod export {
58 pub use libc::{c_char, c_int};
59 pub use openssl_sys::{
60 init, ERR_get_next_error_library, ERR_load_strings, ERR_PACK, ERR_STRING_DATA,
61 };
62 pub use std::borrow::Cow;
63 pub use std::option::Option;
64 pub use std::ptr::null;
65 pub use std::sync::Once;
66 }
67
68 /// An OpenSSL error library.
69 pub trait Library {
70 /// Returns the ID assigned to this library by OpenSSL.
id() -> c_int71 fn id() -> c_int;
72 }
73
74 cfg_if! {
75 if #[cfg(ossl300)] {
76 type FunctionInner = *const c_char;
77 } else {
78 type FunctionInner = c_int;
79 }
80 }
81
82 /// A function declaration, parameterized by its error library.
83 pub struct Function<T>(FunctionInner, PhantomData<T>);
84
85 // manual impls necessary for the 3.0.0 case
86 unsafe impl<T> Sync for Function<T> where T: Sync {}
87 unsafe impl<T> Send for Function<T> where T: Send {}
88
89 impl<T> Function<T> {
90 /// This is not considered a part of the crate's public API, and is subject to change at any time.
91 ///
92 /// # Safety
93 ///
94 /// The inner value must be valid for the lifetime of the process.
95 #[doc(hidden)]
96 #[inline]
__from_raw(raw: FunctionInner) -> Function<T>97 pub const unsafe fn __from_raw(raw: FunctionInner) -> Function<T> {
98 Function(raw, PhantomData)
99 }
100
101 /// This is not considered a part of the crate's public API, and is subject to change at any time.
102 #[doc(hidden)]
103 #[inline]
__as_raw(&self) -> FunctionInner104 pub const fn __as_raw(&self) -> FunctionInner {
105 self.0
106 }
107 }
108
109 /// A reason declaration, parameterized by its error library.
110 pub struct Reason<T>(c_int, PhantomData<T>);
111
112 impl<T> Reason<T> {
113 /// This is not considered a part of the crate's public API, and is subject to change at any time.
114 #[doc(hidden)]
115 #[inline]
__from_raw(raw: c_int) -> Reason<T>116 pub const fn __from_raw(raw: c_int) -> Reason<T> {
117 Reason(raw, PhantomData)
118 }
119
120 /// This is not considered a part of the crate's public API, and is subject to change at any time.
121 #[doc(hidden)]
122 #[inline]
__as_raw(&self) -> c_int123 pub const fn __as_raw(&self) -> c_int {
124 self.0
125 }
126 }
127
128 /// This is not considered part of this crate's public API. It is subject to change at any time.
129 ///
130 /// # Safety
131 ///
132 /// `file` and `message` must be null-terminated.
133 #[doc(hidden)]
__put_error<T>( func: Function<T>, reason: Reason<T>, file: &'static str, line: u32, message: Option<Cow<'static, str>>, ) where T: Library,134 pub unsafe fn __put_error<T>(
135 func: Function<T>,
136 reason: Reason<T>,
137 file: &'static str,
138 line: u32,
139 message: Option<Cow<'static, str>>,
140 ) where
141 T: Library,
142 {
143 put_error_inner(T::id(), func.0, reason.0, file, line, message)
144 }
145
put_error_inner( library: c_int, func: FunctionInner, reason: c_int, file: &'static str, line: u32, message: Option<Cow<'static, str>>, )146 unsafe fn put_error_inner(
147 library: c_int,
148 func: FunctionInner,
149 reason: c_int,
150 file: &'static str,
151 line: u32,
152 message: Option<Cow<'static, str>>,
153 ) {
154 cfg_if! {
155 if #[cfg(ossl300)] {
156 openssl_sys::ERR_new();
157 openssl_sys::ERR_set_debug(
158 file.as_ptr() as *const c_char,
159 line as c_int,
160 func,
161 );
162 openssl_sys::ERR_set_error(library, reason, ptr::null());
163 } else {
164 openssl_sys::ERR_put_error(
165 library,
166 func,
167 reason,
168 file.as_ptr() as *const c_char,
169 line as c_int,
170 );
171 }
172 }
173
174 let data = match message {
175 Some(Cow::Borrowed(s)) => Some((s.as_ptr() as *const c_char as *mut c_char, 0)),
176 Some(Cow::Owned(s)) => {
177 let ptr = openssl_sys::CRYPTO_malloc(
178 s.len() as _,
179 concat!(file!(), "\0").as_ptr() as *const c_char,
180 line!() as c_int,
181 ) as *mut c_char;
182 if ptr.is_null() {
183 None
184 } else {
185 ptr::copy_nonoverlapping(s.as_ptr(), ptr as *mut u8, s.len());
186 Some((ptr, openssl_sys::ERR_TXT_MALLOCED))
187 }
188 }
189 None => None,
190 };
191 if let Some((ptr, flags)) = data {
192 openssl_sys::ERR_set_error_data(ptr, flags | openssl_sys::ERR_TXT_STRING);
193 }
194 }
195
196 /// Pushes an error onto the OpenSSL error stack.
197 ///
198 /// A function and reason are required, and must be associated with the same error library. An additional formatted
199 /// message string can also optionally be provided.
200 #[macro_export]
201 macro_rules! put_error {
202 ($function:expr, $reason:expr) => {
203 unsafe {
204 $crate::__put_error(
205 $function,
206 $reason,
207 concat!(file!(), "\0"),
208 line!(),
209 $crate::export::Option::None,
210 );
211 }
212 };
213 ($function:expr, $reason:expr, $message:expr) => {
214 unsafe {
215 $crate::__put_error(
216 $function,
217 $reason,
218 concat!(file!(), "\0"),
219 line!(),
220 // go through format_args to ensure the message string is handled in the same way as the args case
221 $crate::export::Option::Some($crate::export::Cow::Borrowed(
222 format_args!(concat!($message, "\0")).as_str().unwrap(),
223 )),
224 );
225 }
226 };
227 ($function:expr, $reason:expr, $message:expr, $($args:tt)*) => {
228 unsafe {
229 $crate::__put_error(
230 $function,
231 $reason,
232 concat!(file!(), "\0"),
233 line!(),
234 $crate::export::Option::Some($crate::export::Cow::Owned(
235 format!(concat!($message, "\0"), $($args)*)),
236 ),
237 );
238 }
239 };
240 }
241
242 /// Defines custom OpenSSL error libraries.
243 ///
244 /// The created libraries can be used with the `put_error!` macro to create custom OpenSSL errors.
245 #[macro_export]
246 macro_rules! openssl_errors {
247 ($(
248 $(#[$lib_attr:meta])*
249 $lib_vis:vis library $lib_name:ident($lib_str:expr) {
250 functions {
251 $(
252 $(#[$func_attr:meta])*
253 $func_name:ident($func_str:expr);
254 )*
255 }
256
257 reasons {
258 $(
259 $(#[$reason_attr:meta])*
260 $reason_name:ident($reason_str:expr);
261 )*
262 }
263 }
264 )*) => {$(
265 $(#[$lib_attr])*
266 $lib_vis enum $lib_name {}
267
268 impl $crate::Library for $lib_name {
269 fn id() -> $crate::export::c_int {
270 static INIT: $crate::export::Once = $crate::export::Once::new();
271 static mut LIB_NUM: $crate::export::c_int = 0;
272 $crate::__openssl_errors_helper! {
273 @strings $lib_name($lib_str)
274 functions { $($func_name($func_str);)* }
275 reasons { $($reason_name($reason_str);)* }
276 }
277
278 unsafe {
279 INIT.call_once(|| {
280 $crate::export::init();
281 LIB_NUM = $crate::export::ERR_get_next_error_library();
282 STRINGS[0].error = $crate::export::ERR_PACK(LIB_NUM, 0, 0);
283 $crate::export::ERR_load_strings(LIB_NUM, STRINGS.as_mut_ptr());
284 });
285
286 LIB_NUM
287 }
288 }
289 }
290
291 impl $lib_name {
292 $crate::openssl_errors!(@func_consts $lib_name; 1; $($(#[$func_attr])* $func_name($func_str);)*);
293 $crate::openssl_errors!(@reason_consts $lib_name; 1; $($(#[$reason_attr])* $reason_name;)*);
294 }
295 )*};
296 (@func_consts $lib_name:ident; $n:expr; $(#[$attr:meta])* $name:ident($str:expr); $($tt:tt)*) => {
297 $(#[$attr])*
298 pub const $name: $crate::Function<$lib_name> = unsafe {
299 $crate::Function::__from_raw($crate::__openssl_errors_helper!(@func_value $n, $str))
300 };
301 $crate::openssl_errors!(@func_consts $lib_name; $n + 1; $($tt)*);
302 };
303 (@func_consts $lib_name:ident; $n:expr;) => {};
304 (@reason_consts $lib_name:ident; $n:expr; $(#[$attr:meta])* $name:ident; $($tt:tt)*) => {
305 $(#[$attr])*
306 pub const $name: $crate::Reason<$lib_name> = $crate::Reason::__from_raw($n);
307 $crate::openssl_errors!(@reason_consts $lib_name; $n + 1; $($tt)*);
308 };
309 (@reason_consts $lib_name:ident; $n:expr;) => {};
310 (@count $i:ident; $($tt:tt)*) => {
311 1 + $crate::openssl_errors!(@count $($tt)*)
312 };
313 (@count) => { 0 };
314 }
315
316 cfg_if! {
317 if #[cfg(ossl300)] {
318 #[doc(hidden)]
319 #[macro_export]
320 macro_rules! __openssl_errors_helper {
321 (
322 @strings $lib_name:ident($lib_str:expr)
323 functions { $($func_name:ident($func_str:expr);)* }
324 reasons { $($reason_name:ident($reason_str:expr);)* }
325 ) => {
326 static mut STRINGS: [
327 $crate::export::ERR_STRING_DATA;
328 2 + $crate::openssl_errors!(@count $($reason_name;)*)
329 ] = [
330 $crate::export::ERR_STRING_DATA {
331 error: 0,
332 string: concat!($lib_str, "\0").as_ptr() as *const $crate::export::c_char,
333 },
334 $(
335 $crate::export::ERR_STRING_DATA {
336 error: $crate::export::ERR_PACK(0, 0, $lib_name::$reason_name.__as_raw()),
337 string: concat!($reason_str, "\0").as_ptr() as *const $crate::export::c_char,
338 },
339 )*
340 $crate::export::ERR_STRING_DATA {
341 error: 0,
342 string: $crate::export::null(),
343 }
344 ];
345 };
346 (@func_value $n:expr, $func_str:expr) => {
347 concat!($func_str, "\0").as_ptr() as *const $crate::export::c_char
348 };
349 }
350 } else {
351 #[doc(hidden)]
352 #[macro_export]
353 macro_rules! __openssl_errors_helper {
354 (
355 @strings $lib_name:ident($lib_str:expr)
356 functions { $($func_name:ident($func_str:expr);)* }
357 reasons { $($reason_name:ident($reason_str:expr);)* }
358 ) => {
359 static mut STRINGS: [
360 $crate::export::ERR_STRING_DATA;
361 2 + $crate::openssl_errors!(@count $($func_name;)* $($reason_name;)*)
362 ] = [
363 $crate::export::ERR_STRING_DATA {
364 error: 0,
365 string: concat!($lib_str, "\0").as_ptr() as *const $crate::export::c_char,
366 },
367 $(
368 $crate::export::ERR_STRING_DATA {
369 error: $crate::export::ERR_PACK(0, $lib_name::$func_name.__as_raw(), 0),
370 string: concat!($func_str, "\0").as_ptr() as *const $crate::export::c_char,
371 },
372 )*
373 $(
374 $crate::export::ERR_STRING_DATA {
375 error: $crate::export::ERR_PACK(0, 0, $lib_name::$reason_name.__as_raw()),
376 string: concat!($reason_str, "\0").as_ptr() as *const $crate::export::c_char,
377 },
378 )*
379 $crate::export::ERR_STRING_DATA {
380 error: 0,
381 string: $crate::export::null(),
382 }
383 ];
384 };
385 (@func_value $n:expr, $func_str:expr) => {$n};
386 }
387 }
388 }
389