use std::io::Write;
use anyhow::Context;
use smartstring::{SmartString, LazyCompact};
use super::common::*;
use super::utils::*;
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct AnnounceRequest {
pub info_hash: InfoHash,
pub peer_id: PeerId,
pub port: u16,
pub bytes_left: usize,
pub event: AnnounceEvent,
pub compact: bool,
pub numwant: Option<usize>,
pub key: Option<SmartString<LazyCompact>>,
}
impl AnnounceRequest {
fn write<W: Write>(&self, output: &mut W) -> ::std::io::Result<()> {
output.write_all(b"GET /announce?info_hash=")?;
urlencode_20_bytes(self.info_hash.0, output)?;
output.write_all(b"&peer_id=")?;
urlencode_20_bytes(self.peer_id.0, output)?;
output.write_all(b"&port=")?;
output.write_all(itoa::Buffer::new().format(self.port).as_bytes())?;
output.write_all(b"&uploaded=0&downloaded=0&left=")?;
output.write_all(itoa::Buffer::new().format(self.bytes_left).as_bytes())?;
match self.event {
AnnounceEvent::Started => output.write_all(b"&event=started")?,
AnnounceEvent::Stopped => output.write_all(b"&event=stopped")?,
AnnounceEvent::Completed => output.write_all(b"&event=completed")?,
AnnounceEvent::Empty => (),
};
output.write_all(b"&compact=")?;
output.write_all(itoa::Buffer::new().format(self.compact as u8).as_bytes())?;
if let Some(numwant) = self.numwant {
output.write_all(b"&numwant=")?;
output.write_all(itoa::Buffer::new().format(numwant).as_bytes())?;
}
if let Some(ref key) = self.key {
output.write_all(b"&key=")?;
output.write_all(::urlencoding::encode(key.as_str()).as_bytes())?;
}
output.write_all(b" HTTP/1.1\r\nHost: localhost\r\n\r\n")?;
Ok(())
}
}
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ScrapeRequest {
pub info_hashes: Vec<InfoHash>,
}
impl ScrapeRequest {
fn write<W: Write>(&self, output: &mut W) -> ::std::io::Result<()> {
output.write_all(b"GET /scrape?")?;
let mut first = true;
for info_hash in self.info_hashes.iter() {
if !first {
output.write_all(b"&")?;
}
output.write_all(b"info_hash=")?;
urlencode_20_bytes(info_hash.0, output)?;
first = false;
}
output.write_all(b" HTTP/1.1\r\nHost: localhost\r\n\r\n")?;
Ok(())
}
}
#[derive(Debug)]
pub enum RequestParseError {
NeedMoreData,
Invalid(anyhow::Error),
}
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum Request {
Announce(AnnounceRequest),
Scrape(ScrapeRequest),
}
impl Request {
pub fn from_bytes(bytes: &[u8]) -> Result<Self, RequestParseError> {
let mut headers = [httparse::EMPTY_HEADER; 16];
let mut http_request = httparse::Request::new(&mut headers);
let path = match http_request.parse(bytes){
Ok(httparse::Status::Complete(_)) => {
if let Some(path) = http_request.path {
path
} else {
return Err(RequestParseError::Invalid(
anyhow::anyhow!("no http path")
))
}
},
Ok(httparse::Status::Partial) => {
if let Some(path) = http_request.path {
path
} else {
return Err(RequestParseError::NeedMoreData)
}
}
Err(err) => {
return Err(RequestParseError::Invalid(
anyhow::Error::from(err)
))
},
};
Self::from_http_get_path(path).map_err(RequestParseError::Invalid)
}
pub fn from_http_get_path(path: &str) -> anyhow::Result<Self> {
::log::debug!("request GET path: {}", path);
let mut split_parts= path.splitn(2, '?');
let location = split_parts.next()
.with_context(|| "no location")?;
let query_string = split_parts.next()
.with_context(|| "no query string")?;
let mut info_hashes = Vec::new();
let mut opt_peer_id = None;
let mut opt_port = None;
let mut opt_bytes_left = None;
let mut event = AnnounceEvent::default();
let mut opt_numwant = None;
let mut opt_key = None;
let query_string_bytes = query_string.as_bytes();
let mut ampersand_iter = ::memchr::memchr_iter(b'&', query_string_bytes);
let mut position = 0usize;
for equal_sign_index in ::memchr::memchr_iter(b'=', query_string_bytes){
let segment_end = ampersand_iter.next()
.unwrap_or_else(|| query_string.len());
let key = query_string.get(position..equal_sign_index)
.with_context(|| format!("no key at {}..{}", position, equal_sign_index))?;
let value = query_string.get(equal_sign_index + 1..segment_end)
.with_context(|| format!("no value at {}..{}", equal_sign_index + 1, segment_end))?;
match key {
"info_hash" => {
let value = urldecode_20_bytes(value)?;
info_hashes.push(InfoHash(value));
},
"peer_id" => {
let value = urldecode_20_bytes(value)?;
opt_peer_id = Some(PeerId(value));
},
"port" => {
opt_port = Some(value.parse::<u16>().with_context(|| "parse port")?);
},
"left" => {
opt_bytes_left = Some(value.parse::<usize>().with_context(|| "parse left")?);
},
"event" => {
event = value.parse::<AnnounceEvent>().map_err(|err|
anyhow::anyhow!("invalid event: {}", err)
)?;
},
"compact" => {
if value != "1" {
return Err(anyhow::anyhow!("compact set, but not to 1"));
}
},
"numwant" => {
opt_numwant = Some(value.parse::<usize>().with_context(|| "parse numwant")?);
},
"key" => {
if value.len() > 100 {
return Err(anyhow::anyhow!("'key' is too long"))
}
opt_key = Some(::urlencoding::decode(value)?.into());
},
k => {
::log::debug!("ignored unrecognized key: {}", k)
}
}
if segment_end == query_string.len(){
break
} else {
position = segment_end + 1;
}
}
if location == "/announce" {
let request = AnnounceRequest {
info_hash: info_hashes.pop().with_context(|| "no info_hash")?,
peer_id: opt_peer_id.with_context(|| "no peer_id")?,
port: opt_port.with_context(|| "no port")?,
bytes_left: opt_bytes_left.with_context(|| "no left")?,
event,
compact: true,
numwant: opt_numwant,
key: opt_key,
};
Ok(Request::Announce(request))
} else {
let request = ScrapeRequest {
info_hashes,
};
Ok(Request::Scrape(request))
}
}
pub fn write<W: Write>(&self, output: &mut W) -> ::std::io::Result<()> {
match self {
Self::Announce(r) => r.write(output),
Self::Scrape(r) => r.write(output),
}
}
}
#[cfg(test)]
mod tests {
use quickcheck::{Arbitrary, Gen, TestResult, quickcheck};
use super::*;
static ANNOUNCE_REQUEST_PATH: &str = "/announce?info_hash=%04%0bkV%3f%5cr%14%a6%b7%98%adC%c3%c9.%40%24%00%b9&peer_id=-ABC940-5ert69muw5t8&port=12345&uploaded=0&downloaded=0&left=1&numwant=0&key=4ab4b877&compact=1&supportcrypto=1&event=started";
static SCRAPE_REQUEST_PATH: &str = "/scrape?info_hash=%04%0bkV%3f%5cr%14%a6%b7%98%adC%c3%c9.%40%24%00%b9";
static REFERENCE_INFO_HASH: [u8; 20] = [0x04, 0x0b, b'k', b'V', 0x3f, 0x5c, b'r', 0x14, 0xa6, 0xb7, 0x98, 0xad, b'C', 0xc3, 0xc9, b'.', 0x40, 0x24, 0x00, 0xb9];
static REFERENCE_PEER_ID: [u8; 20] = [b'-', b'A', b'B', b'C', b'9', b'4', b'0', b'-', b'5', b'e', b'r', b't', b'6', b'9', b'm', b'u', b'w', b'5', b't', b'8'];
fn get_reference_announce_request() -> Request {
Request::Announce(AnnounceRequest {
info_hash: InfoHash(REFERENCE_INFO_HASH),
peer_id: PeerId(REFERENCE_PEER_ID),
port: 12345,
bytes_left: 1,
event: AnnounceEvent::Started,
compact: true,
numwant: Some(0),
key: Some("4ab4b877".into())
})
}
#[test]
fn test_announce_request_from_bytes(){
let mut bytes = Vec::new();
bytes.extend_from_slice(b"GET ");
bytes.extend_from_slice(&ANNOUNCE_REQUEST_PATH.as_bytes());
bytes.extend_from_slice(b" HTTP/1.1\r\n\r\n");
let parsed_request = Request::from_bytes(&bytes[..]).unwrap();
let reference_request = get_reference_announce_request();
assert_eq!(parsed_request, reference_request);
}
#[test]
fn test_scrape_request_from_bytes(){
let mut bytes = Vec::new();
bytes.extend_from_slice(b"GET ");
bytes.extend_from_slice(&SCRAPE_REQUEST_PATH.as_bytes());
bytes.extend_from_slice(b" HTTP/1.1\r\n\r\n");
let parsed_request = Request::from_bytes(&bytes[..]).unwrap();
let reference_request = Request::Scrape(ScrapeRequest {
info_hashes: vec![InfoHash(REFERENCE_INFO_HASH)],
});
assert_eq!(parsed_request, reference_request);
}
impl Arbitrary for AnnounceRequest {
fn arbitrary<G: Gen>(g: &mut G) -> Self {
let key: Option<String> = Arbitrary::arbitrary(g);
AnnounceRequest {
info_hash: Arbitrary::arbitrary(g),
peer_id: Arbitrary::arbitrary(g),
port: Arbitrary::arbitrary(g),
bytes_left: Arbitrary::arbitrary(g),
event: Arbitrary::arbitrary(g),
compact: true,
numwant: Arbitrary::arbitrary(g),
key: key.map(|key| key.into()),
}
}
}
impl Arbitrary for ScrapeRequest {
fn arbitrary<G: Gen>(g: &mut G) -> Self {
ScrapeRequest {
info_hashes: Arbitrary::arbitrary(g),
}
}
}
impl Arbitrary for Request {
fn arbitrary<G: Gen>(g: &mut G) -> Self {
if Arbitrary::arbitrary(g){
Self::Announce(Arbitrary::arbitrary(g))
} else {
Self::Scrape(Arbitrary::arbitrary(g))
}
}
}
#[test]
fn quickcheck_serde_identity_request(){
fn prop(request: Request) -> TestResult {
if let Request::Announce(AnnounceRequest { key: Some(ref key), ..}) = request {
if key.len() > 30 {
return TestResult::discard();
}
}
let mut bytes = Vec::new();
request.write(&mut bytes).unwrap();
let parsed_request = Request::from_bytes(&bytes[..]).unwrap();
let success = request == parsed_request;
if !success {
println!("request: {:?}", request);
println!("parsed request: {:?}", parsed_request);
println!("bytes as str: {}", String::from_utf8_lossy(&bytes));
}
TestResult::from_bool(success)
}
quickcheck(prop as fn(Request) -> TestResult);
}
}