diff options
Diffstat (limited to 'src/rust/protover/protover.rs')
| -rw-r--r-- | src/rust/protover/protover.rs | 89 |
1 files changed, 37 insertions, 52 deletions
diff --git a/src/rust/protover/protover.rs b/src/rust/protover/protover.rs index 5e5a31cd33..514aeffc58 100644 --- a/src/rust/protover/protover.rs +++ b/src/rust/protover/protover.rs @@ -3,12 +3,12 @@ use std::collections::HashMap; use std::collections::hash_map; +use std::ffi::CStr; use std::fmt; use std::str; use std::str::FromStr; use std::string::String; -use tor_util::strings::NUL_BYTE; use external::c_tor_version_as_new_as; use errors::ProtoverError; @@ -28,30 +28,6 @@ const FIRST_TOR_VERSION_TO_ADVERTISE_PROTOCOLS: &'static str = "0.2.9.3-alpha"; /// C_RUST_COUPLED: src/or/protover.c `MAX_PROTOCOLS_TO_EXPAND` const MAX_PROTOCOLS_TO_EXPAND: usize = (1<<16); -/// Currently supported protocols and their versions, as a byte-slice. -/// -/// # Warning -/// -/// This byte-slice ends in a NUL byte. This is so that we can directly convert -/// it to an `&'static CStr` in the FFI code, in order to hand the static string -/// to C in a way that is compatible with C static strings. -/// -/// Rust code which wishes to accesses this string should use -/// `protover::get_supported_protocols()` instead. -/// -/// C_RUST_COUPLED: src/or/protover.c `protover_get_supported_protocols` -pub(crate) const SUPPORTED_PROTOCOLS: &'static [u8] = - b"Cons=1-2 \ - Desc=1-2 \ - DirCache=1-2 \ - HSDir=1-2 \ - HSIntro=3-4 \ - HSRend=1-2 \ - Link=1-5 \ - LinkAuth=1,3 \ - Microdesc=1-2 \ - Relay=1-2\0"; - /// Known subprotocols in Tor. Indicates which subprotocol a relay supports. /// /// C_RUST_COUPLED: src/or/protover.h `protocol_type_t` @@ -124,21 +100,33 @@ impl From<Protocol> for UnknownProtocol { } } -/// Get the string representation of current supported protocols +/// Get a CStr representation of current supported protocols, for +/// passing to C, or for converting to a `&str` for Rust. /// /// # Returns /// -/// A `String` whose value is the existing protocols supported by tor. +/// An `&'static CStr` whose value is the existing protocols supported by tor. /// Returned data is in the format as follows: /// /// "HSDir=1-1 LinkAuth=1" /// -pub fn get_supported_protocols() -> &'static str { - // The `len() - 1` is to remove the NUL byte. - // The `unwrap` is safe becauase we SUPPORTED_PROTOCOLS is under - // our control. - str::from_utf8(&SUPPORTED_PROTOCOLS[..SUPPORTED_PROTOCOLS.len() - 1]) - .unwrap_or("") +/// # Note +/// +/// Rust code can use the `&'static CStr` as a normal `&'a str` by +/// calling `protover::get_supported_protocols`. +/// +// C_RUST_COUPLED: src/or/protover.c `protover_get_supported_protocols` +pub(crate) fn get_supported_protocols_cstr() -> &'static CStr { + cstr!("Cons=1-2 \ + Desc=1-2 \ + DirCache=1-2 \ + HSDir=1-2 \ + HSIntro=3-4 \ + HSRend=1-2 \ + Link=1-5 \ + LinkAuth=1,3 \ + Microdesc=1-2 \ + Relay=1-2") } /// A map of protocol names to the versions of them which are supported. @@ -161,7 +149,8 @@ impl ProtoEntry { /// ProtoEntry, which is useful when looking up a specific /// subprotocol. pub fn supported() -> Result<Self, ProtoverError> { - let supported: &'static str = get_supported_protocols(); + let supported_cstr: &'static CStr = get_supported_protocols_cstr(); + let supported: &str = supported_cstr.to_str().unwrap_or(""); supported.parse() } @@ -627,7 +616,7 @@ pub fn is_supported_here(proto: &Protocol, vers: &Version) -> bool { /// /// # Returns /// -/// A `&'static [u8]` encoding a list of protocol names and supported +/// A `&'static CStr` encoding a list of protocol names and supported /// versions. The string takes the following format: /// /// "HSDir=1-1 LinkAuth=1" @@ -643,24 +632,25 @@ pub fn is_supported_here(proto: &Protocol, vers: &Version) -> bool { /// like to use this code in Rust, please see `compute_for_old_tor()`. // // C_RUST_COUPLED: src/rust/protover.c `compute_for_old_tor` -pub(crate) fn compute_for_old_tor_cstr(version: &str) -> &'static [u8] { +pub(crate) fn compute_for_old_tor_cstr(version: &str) -> &'static CStr { + let empty: &'static CStr = cstr!(""); + if c_tor_version_as_new_as(version, FIRST_TOR_VERSION_TO_ADVERTISE_PROTOCOLS) { - return NUL_BYTE; + return empty; } if c_tor_version_as_new_as(version, "0.2.9.1-alpha") { - return b"Cons=1-2 Desc=1-2 DirCache=1 HSDir=1 HSIntro=3 HSRend=1-2 \ - Link=1-4 LinkAuth=1 Microdesc=1-2 Relay=1-2\0"; + return cstr!("Cons=1-2 Desc=1-2 DirCache=1 HSDir=1 HSIntro=3 HSRend=1-2 \ + Link=1-4 LinkAuth=1 Microdesc=1-2 Relay=1-2"); } if c_tor_version_as_new_as(version, "0.2.7.5") { - return b"Cons=1-2 Desc=1-2 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 \ - Link=1-4 LinkAuth=1 Microdesc=1-2 Relay=1-2\0"; + return cstr!("Cons=1-2 Desc=1-2 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 \ + Link=1-4 LinkAuth=1 Microdesc=1-2 Relay=1-2"); } if c_tor_version_as_new_as(version, "0.2.4.19") { - return b"Cons=1 Desc=1 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 \ - Link=1-4 LinkAuth=1 Microdesc=1 Relay=1-2\0"; + return cstr!("Cons=1 Desc=1 DirCache=1 HSDir=1 HSIntro=3 HSRend=1 \ + Link=1-4 LinkAuth=1 Microdesc=1 Relay=1-2"); } - - NUL_BYTE + empty } /// Since older versions of Tor cannot infer their own subprotocols, @@ -691,14 +681,9 @@ pub(crate) fn compute_for_old_tor_cstr(version: &str) -> &'static [u8] { // // C_RUST_COUPLED: src/rust/protover.c `compute_for_old_tor` pub fn compute_for_old_tor(version: &str) -> Result<&'static str, ProtoverError> { - let mut computed: &'static [u8] = compute_for_old_tor_cstr(version); - - // Remove the NULL byte at the end. - computed = &computed[..computed.len() - 1]; - - // .from_utf8() fails with a Utf8Error if it couldn't validate the + // .to_str() fails with a Utf8Error if it couldn't validate the // utf-8, so convert that here into an Unparseable ProtoverError. - str::from_utf8(computed).or(Err(ProtoverError::Unparseable)) + compute_for_old_tor_cstr(version).to_str().or(Err(ProtoverError::Unparseable)) } #[cfg(test)] |