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tor_rpc_connect/
lib.rs

1#![cfg_attr(docsrs, feature(doc_cfg))]
2#![doc = include_str!("../README.md")]
3// @@ begin lint list maintained by maint/add_warning @@
4#![allow(renamed_and_removed_lints)] // @@REMOVE_WHEN(ci_arti_stable)
5#![allow(unknown_lints)] // @@REMOVE_WHEN(ci_arti_nightly)
6#![warn(missing_docs)]
7#![warn(noop_method_call)]
8#![warn(unreachable_pub)]
9#![warn(clippy::all)]
10#![deny(clippy::await_holding_lock)]
11#![deny(clippy::cargo_common_metadata)]
12#![deny(clippy::cast_lossless)]
13#![deny(clippy::checked_conversions)]
14#![warn(clippy::cognitive_complexity)]
15#![deny(clippy::debug_assert_with_mut_call)]
16#![deny(clippy::exhaustive_enums)]
17#![deny(clippy::exhaustive_structs)]
18#![deny(clippy::expl_impl_clone_on_copy)]
19#![deny(clippy::fallible_impl_from)]
20#![deny(clippy::implicit_clone)]
21#![deny(clippy::large_stack_arrays)]
22#![warn(clippy::manual_ok_or)]
23#![deny(clippy::missing_docs_in_private_items)]
24#![warn(clippy::needless_borrow)]
25#![warn(clippy::needless_pass_by_value)]
26#![warn(clippy::option_option)]
27#![deny(clippy::print_stderr)]
28#![deny(clippy::print_stdout)]
29#![warn(clippy::rc_buffer)]
30#![deny(clippy::ref_option_ref)]
31#![warn(clippy::semicolon_if_nothing_returned)]
32#![warn(clippy::trait_duplication_in_bounds)]
33#![deny(clippy::unchecked_time_subtraction)]
34#![deny(clippy::unnecessary_wraps)]
35#![warn(clippy::unseparated_literal_suffix)]
36#![deny(clippy::unwrap_used)]
37#![deny(clippy::mod_module_files)]
38#![allow(clippy::let_unit_value)] // This can reasonably be done for explicitness
39#![allow(clippy::uninlined_format_args)]
40#![allow(clippy::significant_drop_in_scrutinee)] // arti/-/merge_requests/588/#note_2812945
41#![allow(clippy::result_large_err)] // temporary workaround for arti#587
42#![allow(clippy::needless_raw_string_hashes)] // complained-about code is fine, often best
43#![allow(clippy::needless_lifetimes)] // See arti#1765
44#![allow(mismatched_lifetime_syntaxes)] // temporary workaround for arti#2060
45#![allow(clippy::collapsible_if)] // See arti#2342
46#![deny(clippy::unused_async)]
47//! <!-- @@ end lint list maintained by maint/add_warning @@ -->
48
49// TODO #1645 (either remove this, or decide to have it everywhere)
50#![cfg_attr(not(all(feature = "full")), allow(unused))]
51
52pub mod auth;
53#[cfg(feature = "rpc-client")]
54pub mod client;
55mod connpt;
56pub mod load;
57#[cfg(feature = "rpc-server")]
58pub mod server;
59#[cfg(test)]
60mod testing;
61
62use std::{io, sync::Arc};
63
64pub use connpt::{ParsedConnectPoint, ResolveError, ResolvedConnectPoint};
65use tor_general_addr::general;
66
67/// An action that an RPC client should take when a connect point fails.
68///
69/// (This terminology is taken from the spec.)
70#[derive(Clone, Copy, Debug, Eq, PartialEq)]
71#[allow(clippy::exhaustive_enums)]
72pub enum ClientErrorAction {
73    /// The client must stop, and must not make any more connect attempts.
74    Abort,
75    /// The connect point has failed; the client can continue to the next connect point.
76    Decline,
77}
78/// An error that has a [`ClientErrorAction`].
79pub trait HasClientErrorAction {
80    /// Return the action that an RPC client should take based on this error.
81    fn client_action(&self) -> ClientErrorAction;
82}
83impl HasClientErrorAction for tor_config_path::CfgPathError {
84    fn client_action(&self) -> ClientErrorAction {
85        // Every variant of this means a configuration error
86        // or an ill-formed TOML file.
87        ClientErrorAction::Abort
88    }
89}
90impl HasClientErrorAction for tor_config_path::addr::CfgAddrError {
91    fn client_action(&self) -> ClientErrorAction {
92        use ClientErrorAction as A;
93        use tor_config_path::addr::CfgAddrError as CAE;
94        match self {
95            CAE::NoAfUnixSocketSupport(_) => A::Decline,
96            CAE::Path(cfg_path_error) => cfg_path_error.client_action(),
97            CAE::ConstructAfUnixAddress(_) => A::Abort,
98            // No variants are currently captured in this pattern, but they _could_ be in the future.
99            _ => A::Abort,
100        }
101    }
102}
103impl HasClientErrorAction for tor_general_addr::general::AddrParseError {
104    fn client_action(&self) -> ClientErrorAction {
105        use ClientErrorAction as A;
106        use tor_general_addr::general::AddrParseError as E;
107        match self {
108            E::UnrecognizedSchema(_) => A::Decline,
109            E::NoSchema => A::Decline,
110            E::InvalidAfUnixAddress(_) => A::Abort,
111            // We might want to turn this into an Abort in the future, but I think that we might
112            // want to allow "auto" as a port format in CfgAddr.
113            E::InvalidInetAddress(_) => A::Decline,
114            // No variants are currently captured in this pattern, but they _could_ be in the future.
115            _ => A::Abort,
116        }
117    }
118}
119
120/// Return the ClientErrorAction for an IO error encountered
121/// while accessing the filesystem.
122///
123/// Note that this is not an implementation of `HasClientErrorAction`:
124/// We want to decline on a different set of errors for network operation.
125fn fs_error_action(err: &std::io::Error) -> ClientErrorAction {
126    use ClientErrorAction as A;
127    use std::io::ErrorKind as EK;
128    match err.kind() {
129        EK::NotFound => A::Decline,
130        EK::PermissionDenied => A::Decline,
131        _ => A::Abort,
132    }
133}
134/// Return the ClientErrorAction for an IO error encountered
135/// while opening a socket.
136///
137/// Note that this is not an implementation of `HasClientErrorAction`:
138/// We want to decline on a different set of errors for fs operation.
139fn net_error_action(err: &std::io::Error) -> ClientErrorAction {
140    use ClientErrorAction as A;
141    use std::io::ErrorKind as EK;
142    match err.kind() {
143        EK::ConnectionRefused => A::Decline,
144        EK::ConnectionReset => A::Decline,
145        // TODO MSRV 1.83; revisit once some of `io_error_more` is stabilized.
146        // see https://github.com/rust-lang/rust/pull/128316
147        _ => A::Abort,
148    }
149}
150impl HasClientErrorAction for fs_mistrust::Error {
151    fn client_action(&self) -> ClientErrorAction {
152        use ClientErrorAction as A;
153        use fs_mistrust::Error as E;
154        match self {
155            E::Multiple(errs) => {
156                if errs.iter().any(|e| e.client_action() == A::Abort) {
157                    A::Abort
158                } else {
159                    A::Decline
160                }
161            }
162            E::Io { err, .. } => fs_error_action(err),
163            E::CouldNotInspect(_, err) => fs_error_action(err),
164
165            E::NotFound(_) => A::Decline,
166            E::BadPermission(_, _, _) | E::BadOwner(_, _) => A::Decline,
167            E::StepsExceeded | E::CurrentDirectory(_) => A::Abort,
168
169            E::BadType(_) => A::Abort,
170
171            // These should be impossible for clients given how we use fs_mistrust in this crate.
172            E::CreatingDir(_)
173            | E::Content(_)
174            | E::NoSuchGroup(_)
175            | E::NoSuchUser(_)
176            | E::MissingField(_)
177            | E::InvalidSubdirectory => A::Abort,
178            E::PasswdGroupIoError(_) => A::Abort,
179            _ => A::Abort,
180        }
181    }
182}
183
184/// A failure to connect or bind to a [`ResolvedConnectPoint`].
185#[derive(Clone, Debug, thiserror::Error)]
186#[non_exhaustive]
187pub enum ConnectError {
188    /// We encountered an IO error while actually opening our socket.
189    #[error("IO error while connecting")]
190    Io(#[source] Arc<io::Error>),
191    /// The connect point told us to abort explicitly.
192    #[error("Encountered an explicit \"abort\"")]
193    ExplicitAbort,
194    /// We couldn't load the cookie file for cookie authentication.
195    #[error("Unable to load cookie file")]
196    LoadCookie(#[from] auth::cookie::CookieAccessError),
197    /// We were told to connect to a socket type that we don't support.
198    #[error("Unsupported socket type")]
199    UnsupportedSocketType,
200    /// We were told to connect using an auth type that we don't support.
201    #[error("Unsupported authentication type")]
202    UnsupportedAuthType,
203    /// Unable to access the location of an AF\_UNIX socket.
204    #[error("Unix domain socket path access")]
205    AfUnixSocketPathAccess(#[from] fs_mistrust::Error),
206    /// Unable to access the location of `socket_address_file`.
207    #[error("Problem accessing socket address file")]
208    SocketAddressFileAccess(#[source] fs_mistrust::Error),
209    /// We couldn't parse the JSON contents of a socket address file.
210    #[error("Invalid JSON contents in socket address file")]
211    SocketAddressFileJson(#[source] Arc<serde_json::Error>),
212    /// We couldn't parse the address in a socket address file.
213    #[error("Invalid address in socket address file")]
214    SocketAddressFileContent(#[source] general::AddrParseError),
215    /// We found an address in the socket address file that didn't match the connect point.
216    #[error("Socket address file contents didn't match connect point")]
217    SocketAddressFileMismatch,
218    /// Another process was holding a lock for this connect point,
219    /// so we couldn't bind to it.
220    #[error("Could not acquire lock: Another process is listening on this connect point")]
221    AlreadyLocked,
222    /// We encountered an internal logic error.
223    //
224    // (We're not using tor_error::Bug here because we want this code to work properly in rpc-client-core.)
225    #[error("Internal error: {0}")]
226    Internal(String),
227}
228
229impl From<io::Error> for ConnectError {
230    fn from(err: io::Error) -> Self {
231        ConnectError::Io(Arc::new(err))
232    }
233}
234impl crate::HasClientErrorAction for ConnectError {
235    fn client_action(&self) -> crate::ClientErrorAction {
236        use crate::ClientErrorAction as A;
237        use ConnectError as E;
238        match self {
239            E::Io(err) => crate::net_error_action(err),
240            E::ExplicitAbort => A::Abort,
241            E::LoadCookie(err) => err.client_action(),
242            E::UnsupportedSocketType => A::Decline,
243            E::UnsupportedAuthType => A::Decline,
244            E::AfUnixSocketPathAccess(err) => err.client_action(),
245            E::SocketAddressFileAccess(err) => err.client_action(),
246            E::SocketAddressFileJson(_) => A::Decline,
247            E::SocketAddressFileContent(_) => A::Decline,
248            E::SocketAddressFileMismatch => A::Decline,
249            E::AlreadyLocked => A::Abort, // (This one can't actually occur for clients.)
250            E::Internal(_) => A::Abort,
251        }
252    }
253}
254#[cfg(any(feature = "rpc-client", feature = "rpc-server"))]
255/// Given a `general::SocketAddr`, try to return the path of its parent directory (if any).
256fn socket_parent_path(addr: &tor_general_addr::general::SocketAddr) -> Option<&std::path::Path> {
257    addr.as_pathname().and_then(|p| p.parent())
258}
259
260/// Default connect point for a user-owned Arti instance.
261pub const USER_DEFAULT_CONNECT_POINT: &str = {
262    cfg_if::cfg_if! {
263        if #[cfg(unix)] {
264r#"
265[connect]
266socket = "unix:${ARTI_LOCAL_DATA}/rpc/arti_rpc_socket"
267auth = "none"
268"#
269        } else {
270r#"
271[connect]
272socket = "inet:127.0.0.1:9180"
273auth = { cookie = { path = "${ARTI_LOCAL_DATA}/rpc/arti_rpc_cookie" } }
274"#
275        }
276    }
277};
278
279/// Default connect point for a system-wide Arti instance.
280///
281/// This is `None` if, on this platform, there is no such default connect point.
282pub const SYSTEM_DEFAULT_CONNECT_POINT: Option<&str> = {
283    cfg_if::cfg_if! {
284        if #[cfg(unix)] {
285            Some(
286r#"
287[connect]
288socket = "unix:/var/run/arti-rpc/arti_rpc_socket"
289auth = "none"
290"#
291            )
292        } else {
293            None
294        }
295    }
296};
297
298/// An enum to reflect whether an authenticated connection to a connect point is allowed to acquire
299/// superuser (admin) capabilities.
300#[derive(Copy, Clone, Debug, PartialEq, Eq)]
301#[non_exhaustive]
302pub enum SuperuserPermission {
303    /// The connection may acquire superuser capabilities.
304    Allowed,
305    /// The connection may not acquire superuser capabilities.
306    NotAllowed,
307}
308
309#[cfg(test)]
310mod test {
311    // @@ begin test lint list maintained by maint/add_warning @@
312    #![allow(clippy::bool_assert_comparison)]
313    #![allow(clippy::clone_on_copy)]
314    #![allow(clippy::dbg_macro)]
315    #![allow(clippy::mixed_attributes_style)]
316    #![allow(clippy::print_stderr)]
317    #![allow(clippy::print_stdout)]
318    #![allow(clippy::single_char_pattern)]
319    #![allow(clippy::unwrap_used)]
320    #![allow(clippy::unchecked_time_subtraction)]
321    #![allow(clippy::useless_vec)]
322    #![allow(clippy::needless_pass_by_value)]
323    //! <!-- @@ end test lint list maintained by maint/add_warning @@ -->
324
325    use super::*;
326
327    #[test]
328    fn parse_defaults() {
329        let _parsed: ParsedConnectPoint = USER_DEFAULT_CONNECT_POINT.parse().unwrap();
330        if let Some(s) = SYSTEM_DEFAULT_CONNECT_POINT {
331            let _parsed: ParsedConnectPoint = s.parse().unwrap();
332        }
333    }
334}