Unverified Commit 3c4e006e authored by Isis Lovecruft's avatar Isis Lovecruft
Browse files

rust: Use tor_util::strings utils for protover_get_supported_protocols.

parent 8fff331b

src/rust/protover/ffi.rs

+1 −13
Original line number Diff line number Diff line
@@ -15,7 +15,6 @@ use tor_allocate::allocate_and_copy_string; 
use tor_util::strings::byte_slice_is_c_like;

use tor_util::strings::empty_static_cstr;





/// Translate C enums to Rust Proto enums, using the integer value of the C

/// enum to map to its associated Rust enum

///
@@ -143,18 +142,7 @@ pub extern "C" fn protocol_list_supports_protocol_or_later( 
pub extern "C" fn protover_get_supported_protocols() -> *const c_char {

    let supported: &'static CStr;



    // If we're going to pass it to C, there cannot be any intermediate NUL

    // bytes.  An assert is okay here, since changing the const byte slice

    // in protover.rs to contain a NUL byte somewhere in the middle would be a

    // programming error.

    assert!(byte_slice_is_c_like(SUPPORTED_PROTOCOLS));



    // It's okay to unwrap the result of this function because

    // we can see that the bytes we're passing into it 1) are valid UTF-8,

    // 2) have no intermediate NUL bytes, and 3) are terminated with a NUL

    // byte.

    supported = CStr::from_bytes_with_nul(SUPPORTED_PROTOCOLS).unwrap();



    supported = get_supported_protocols_cstr();

    supported.as_ptr()

}

src/rust/protover/lib.rs

+1 −0
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ extern crate libc; 
extern crate smartlist;

extern crate external;

extern crate tor_allocate;

#[macro_use]

extern crate tor_util;



mod protover;

src/rust/protover/protover.rs

+39 −32
Original line number Diff line number Diff line
@@ -5,6 +5,7 @@ use external::c_tor_version_as_new_as; 


use std::str;

use std::str::FromStr;

use std::ffi::CStr;

use std::fmt;

use std::collections::{HashMap, HashSet};

use std::ops::Range;
@@ -25,30 +26,6 @@ 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: u32 = 500;



/// 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`
@@ -96,21 +73,51 @@ impl FromStr for Proto { 
    }

}



/// 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")

}



/// Get a string representation of current supported protocols.

///

/// # Returns

///

/// An `&'a str` 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<'a>() -> &'a str {

    let supported_cstr: &'static CStr = get_supported_protocols_cstr();

    let supported: &str = match supported_cstr.to_str() {

        Ok(x)  => x,

        Err(_) => "",

    };



    supported

}



pub struct SupportedProtocols(HashMap<Proto, Versions>);