rust: Add new protover::ProtoEntry type which uses new datatypes.

This replaces the `protover::SupportedProtocols` (why would you have a type just
for things which are supported?) with a new, more generic type,
`protover::ProtoEntry`, which utilises the new, more memory-efficient datatype
in protover::protoset.

 * REMOVE `get_supported_protocols()` and `SupportedProtocols::tor_supported()`
   (since they were never used separately) and collapse their functionality into
   a single `ProtoEntry::supported()` method.
 * REMOVE `SupportedProtocols::from_proto_entries()` and reimplement its
   functionality as the more rusty `impl FromStr for ProtoEntry`.
 * REMOVE `get_proto_and_vers()` function and refactor it into the more rusty
   `impl FromStr for ProtoEntry`.
 * FIXES part of #24031: https://bugs.torproject.org/24031
This commit is contained in:
Isis Lovecruft 2018-03-21 01:18:02 +00:00
parent 60daaa68b1
commit 54c964332b
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@ -1,20 +1,19 @@
// Copyright (c) 2016-2017, The Tor Project, Inc. */
// See LICENSE for licensing information */
use external::c_tor_version_as_new_as;
use std::collections::HashMap;
use std::collections::hash_map;
use std::fmt;
use std::str;
use std::str::FromStr;
use std::fmt;
use std::collections::{HashMap, HashSet};
use std::ops::Range;
use std::string::String;
use std::u32;
use tor_util::strings::NUL_BYTE;
use external::c_tor_version_as_new_as;
use errors::ProtoverError;
use protoset::Version;
use protoset::ProtoSet;
/// The first version of Tor that included "proto" entries in its descriptors.
/// Authorities should use this to decide whether to guess proto lines.
@ -142,82 +141,89 @@ pub fn get_supported_protocols() -> &'static str {
.unwrap_or("")
}
pub struct SupportedProtocols(HashMap<Proto, Versions>);
/// A map of protocol names to the versions of them which are supported.
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct ProtoEntry(HashMap<Protocol, ProtoSet>);
impl SupportedProtocols {
pub fn from_proto_entries<I, S>(protocol_strs: I) -> Result<Self, &'static str>
where
I: Iterator<Item = S>,
S: AsRef<str>,
{
let mut parsed = HashMap::new();
for subproto in protocol_strs {
let (name, version) = get_proto_and_vers(subproto.as_ref())?;
parsed.insert(name, version);
}
Ok(SupportedProtocols(parsed))
}
/// Translates a string representation of a protocol list to a
/// SupportedProtocols instance.
///
/// # Examples
///
/// ```
/// use protover::SupportedProtocols;
///
/// let supported_protocols = SupportedProtocols::from_proto_entries_string(
/// "HSDir=1-2 HSIntro=3-4"
/// );
/// ```
pub fn from_proto_entries_string(
proto_entries: &str,
) -> Result<Self, &'static str> {
Self::from_proto_entries(proto_entries.split(" "))
}
/// Translate the supported tor versions from a string into a
/// HashMap, which is useful when looking up a specific
/// subprotocol.
///
fn tor_supported() -> Result<Self, &'static str> {
Self::from_proto_entries_string(get_supported_protocols())
impl Default for ProtoEntry {
fn default() -> ProtoEntry {
ProtoEntry( HashMap::new() )
}
}
/// Parse the subprotocol type and its version numbers.
///
/// # Inputs
///
/// * A `protocol_entry` string, comprised of a keyword, an "=" sign, and one
/// or more version numbers.
///
/// # Returns
///
/// A `Result` whose `Ok` value is a tuple of `(Proto, HashSet<u32>)`, where the
/// first element is the subprotocol type (see `protover::Proto`) and the last
/// element is a(n unordered) set of unique version numbers which are supported.
/// Otherwise, the `Err` value of this `Result` is a description of the error
///
fn get_proto_and_vers<'a>(
protocol_entry: &'a str,
) -> Result<(Proto, Versions), &'static str> {
let mut parts = protocol_entry.splitn(2, "=");
impl ProtoEntry {
/// Get an iterator over the `Protocol`s and their `ProtoSet`s in this `ProtoEntry`.
pub fn iter(&self) -> hash_map::Iter<Protocol, ProtoSet> {
self.0.iter()
}
let proto = match parts.next() {
Some(n) => n,
None => return Err("invalid protover entry"),
};
/// Translate the supported tor versions from a string into a
/// ProtoEntry, which is useful when looking up a specific
/// subprotocol.
pub fn supported() -> Result<Self, ProtoverError> {
let supported: &'static str = get_supported_protocols();
let vers = match parts.next() {
Some(n) => n,
None => return Err("invalid protover entry"),
};
supported.parse()
}
let versions = Versions::from_version_string(vers)?;
let proto_name = proto.parse()?;
pub fn get(&self, protocol: &Protocol) -> Option<&ProtoSet> {
self.0.get(protocol)
}
Ok((proto_name, versions))
pub fn insert(&mut self, key: Protocol, value: ProtoSet) {
self.0.insert(key, value);
}
pub fn remove(&mut self, key: &Protocol) -> Option<ProtoSet> {
self.0.remove(key)
}
pub fn is_empty(&self) -> bool {
self.0.is_empty()
}
}
impl FromStr for ProtoEntry {
type Err = ProtoverError;
/// Parse a string of subprotocol types and their version numbers.
///
/// # Inputs
///
/// * A `protocol_entry` string, comprised of a keywords, an "=" sign, and
/// one or more version numbers, each separated by a space. For example,
/// `"Cons=3-4 HSDir=1"`.
///
/// # Returns
///
/// A `Result` whose `Ok` value is a `ProtoEntry`, where the
/// first element is the subprotocol type (see `protover::Protocol`) and the last
/// element is an ordered set of `(low, high)` unique version numbers which are supported.
/// Otherwise, the `Err` value of this `Result` is a `ProtoverError`.
fn from_str(protocol_entry: &str) -> Result<ProtoEntry, ProtoverError> {
let mut proto_entry: ProtoEntry = ProtoEntry::default();
let entries = protocol_entry.split(' ');
for entry in entries {
let mut parts = entry.splitn(2, '=');
let proto = match parts.next() {
Some(n) => n,
None => return Err(ProtoverError::Unparseable),
};
let vers = match parts.next() {
Some(n) => n,
None => return Err(ProtoverError::Unparseable),
};
let versions: ProtoSet = vers.parse()?;
let proto_name: Protocol = proto.parse()?;
proto_entry.insert(proto_name, versions);
}
Ok(proto_entry)
}
}
/// Parses a single subprotocol entry string into subprotocol and version