Add SRTP server example

Cargo.toml

@@ -9,3 +9,8 @@ handy_async = "0.2"
 rust-crypto = "0.2"
 num = "0.1"
 splay_tree = "0.2"
+
+[dev-dependencies]
+clap = "2"
+fibers = "0.1"
+futures = "0.1"

examples/srtpsrv.rs

@@ -0,0 +1,79 @@
+extern crate clap;
+extern crate fibers;
+extern crate futures;
+#[macro_use]
+extern crate trackable;
+extern crate rtp;
+
+use clap::{App, Arg};
+use fibers::{Spawn, Executor, InPlaceExecutor};
+use fibers::net::UdpSocket;
+use fibers::net::futures::RecvFrom;
+use futures::{Future, Poll, Async};
+use trackable::error::ErrorKindExt;
+use rtp::{Error, ErrorKind};
+use rtp::traits::ReadPacket;
+use rtp::rfc3550::RtpPacketReader;
+use rtp::rfc3711::{SrtpPacketReader, SrtpContext};
+
+fn main() {
+    let matches = App::new("srtpsrv")
+        .arg(Arg::with_name("PORT").short("p").takes_value(true).default_value("6000"))
+        .arg(Arg::with_name("MASTER_KEY").short("k").takes_value(true)
+             .default_value("d34d74f37d74e75f3bdb4f76f1bdf477"))
+        .arg(Arg::with_name("MASTER_SALT").short("s").takes_value(true)
+             .default_value("7f1fe35d78f77e75e79f7beb5f7a"))
+        .get_matches();
+    let port = matches.value_of("PORT").unwrap();
+    let addr = format!("0.0.0.0:{}", port).parse().unwrap();
+
+    let master_key = hex_str_to_bytes(matches.value_of("MASTER_KEY").unwrap());
+    let master_salt = hex_str_to_bytes(matches.value_of("MASTER_SALT").unwrap());
+    let context = SrtpContext::new(&master_key, &master_salt);
+    let future = track_err!(UdpSocket::bind(addr)).and_then(move |socket| {
+                                                                SrtpRecvLoop::new(socket, context)
+                                                            });
+
+    let mut executor = InPlaceExecutor::new().unwrap();
+    let monitor = executor.spawn_monitor(future);
+    let result = executor.run_fiber(monitor).unwrap()
+        .map_err(|e| e.unwrap_or_else(|| ErrorKind::Other.cause("disconnected")));
+    track_try_unwrap!(result);
+}
+
+fn hex_str_to_bytes(s: &str) -> Vec<u8> {
+    use std::u8;
+    let mut bytes = Vec::new();
+    for i in 0..s.len() / 2 {
+        let b = u8::from_str_radix(&s[i * 2..i * 2 + 2], 16).unwrap();
+        bytes.push(b);
+    }
+    bytes
+}
+
+struct SrtpRecvLoop {
+    future: RecvFrom<Vec<u8>>,
+    reader: SrtpPacketReader<RtpPacketReader>,
+}
+impl SrtpRecvLoop {
+    fn new(socket: UdpSocket, context: SrtpContext) -> Self {
+        let inner = RtpPacketReader;
+        SrtpRecvLoop {
+            future: socket.recv_from(vec![0; 4096]),
+            reader: SrtpPacketReader::new(context, inner),
+        }
+    }
+}
+impl Future for SrtpRecvLoop {
+    type Item = ();
+    type Error = Error;
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        while let Async::Ready(v) = track_try!(self.future.poll().map_err(|e| e.2)) {
+            let (socket, buf, size, peer) = v;
+            let packet = track_try!(self.reader.read_packet(&mut &buf[..size]));
+            println!("Recv packet from {}: {:?}", peer, packet);
+            self.future = socket.recv_from(buf);
+        }
+        Ok(Async::NotReady)
+    }
+}

src/rfc5761.rs

@@ -1,6 +1,6 @@
 use std::io::{Read, Write};
 
-use {Result};
+use Result;
 use traits::{ReadPacket, WritePacket, RtpPacket, RtcpPacket, Packet};
 
 #[derive(Debug, Clone, PartialEq, Eq)]