transport.rs

  1use std::io::prelude::*;
  2
  3use std::net::TcpStream;
  4
  5use xml::reader::{EventReader, XmlEvent as XmlReaderEvent};
  6use xml::writer::{EventWriter, XmlEvent as XmlWriterEvent, EmitterConfig};
  7
  8use std::sync::{Arc, Mutex};
  9
 10use ns;
 11
 12use minidom;
 13
 14use locked_io::LockedIO;
 15
 16use error::Error;
 17
 18use openssl::ssl::{SslMethod, SslConnectorBuilder, SslStream};
 19
 20pub trait Transport {
 21    fn write_event<'a, E: Into<XmlWriterEvent<'a>>>(&mut self, event: E) -> Result<(), Error>;
 22    fn read_event(&mut self) -> Result<XmlReaderEvent, Error>;
 23
 24    fn write_element(&mut self, element: &minidom::Element) -> Result<(), Error>;
 25    fn read_element(&mut self) -> Result<minidom::Element, Error>;
 26
 27    fn reset_stream(&mut self);
 28}
 29
 30pub struct SslTransport {
 31    inner: Arc<Mutex<SslStream<TcpStream>>>, // TODO: this feels rather ugly
 32    reader: EventReader<LockedIO<SslStream<TcpStream>>>, // TODO: especially feels ugly because
 33                                                         //       this read would keep the lock
 34                                                         //       held very long (potentially)
 35    writer: EventWriter<LockedIO<SslStream<TcpStream>>>,
 36}
 37
 38impl Transport for SslTransport {
 39    fn write_event<'a, E: Into<XmlWriterEvent<'a>>>(&mut self, event: E) -> Result<(), Error> {
 40        Ok(self.writer.write(event)?)
 41    }
 42
 43    fn read_event(&mut self) -> Result<XmlReaderEvent, Error> {
 44        Ok(self.reader.next()?)
 45    }
 46
 47    fn write_element(&mut self, element: &minidom::Element) -> Result<(), Error> {
 48        Ok(element.write_to(&mut self.writer)?)
 49    }
 50
 51    fn read_element(&mut self) -> Result<minidom::Element, Error> {
 52        Ok(minidom::Element::from_reader(&mut self.reader)?)
 53    }
 54
 55    fn reset_stream(&mut self) {
 56        let locked_io = LockedIO::from(self.inner.clone());
 57        self.reader = EventReader::new(locked_io.clone());
 58        self.writer = EventWriter::new_with_config(locked_io, EmitterConfig {
 59            line_separator: "".into(),
 60            perform_indent: false,
 61            normalize_empty_elements: false,
 62            .. Default::default()
 63        });
 64    }
 65}
 66
 67impl SslTransport {
 68    pub fn connect(host: &str, port: u16) -> Result<SslTransport, Error> {
 69        // TODO: very quick and dirty, blame starttls
 70        let mut stream = TcpStream::connect((host, port))?;
 71        write!(stream, "<stream:stream xmlns='{}' xmlns:stream='{}' to='{}' version='1.0'>"
 72                     , ns::CLIENT, ns::STREAM, host)?;
 73        write!(stream, "<starttls xmlns='{}'/>"
 74                     , ns::TLS)?;
 75        let mut parser = EventReader::new(stream);
 76        loop { // TODO: possibly a timeout?
 77            match parser.next()? {
 78                XmlReaderEvent::StartElement { name, .. } => {
 79                    if let Some(ns) = name.namespace {
 80                        if ns == ns::TLS && name.local_name == "proceed" {
 81                            break;
 82                        }
 83                        else if ns == ns::STREAM && name.local_name == "error" {
 84                            return Err(Error::StreamError);
 85                        }
 86                    }
 87                },
 88                _ => {},
 89            }
 90        }
 91        let stream = parser.into_inner();
 92        let ssl_connector = SslConnectorBuilder::new(SslMethod::tls())?.build();
 93        let ssl_stream = Arc::new(Mutex::new(ssl_connector.connect(host, stream)?));
 94        let locked_io = LockedIO::from(ssl_stream.clone());
 95        let reader = EventReader::new(locked_io.clone());
 96        let writer = EventWriter::new_with_config(locked_io, EmitterConfig {
 97            line_separator: "".into(),
 98            perform_indent: false,
 99            normalize_empty_elements: false,
100            .. Default::default()
101        });
102        Ok(SslTransport {
103            inner: ssl_stream,
104            reader: reader,
105            writer: writer,
106        })
107    }
108
109    pub fn close(&mut self) {
110        self.inner.lock()
111                  .unwrap()
112                  .shutdown()
113                  .unwrap(); // TODO: safety, return value and such
114    }
115}