Clean and refactor server's inner loop

6 files changed, 151 insertions, 147 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9a98044..343aa58 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## version 1.1.2
+
+* Optional client request statistics tracking.
+* Clean-up and simplification of server inner loop.
+
 ## Version 1.1.1
 
 * Provide auxiliary data to the AWS KMS decryption call. The auxiliary data _was_ provided in encrypt, but not decrypt, resulting in unconditional failure when unwrapping the long-term identity. See https://github.com/int08h/roughenough/commit/846128d08bd3fcd72f23b3123b332d0692782e41#diff-7f7c3059af30a5ded26269301caf8531R102
diff --git a/Cargo.toml b/Cargo.toml
index 165d81d..fa57435 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "roughenough"
-version = "1.1.1"
+version = "1.1.2"
 repository = "https://github.com/int08h/roughenough"
 authors = ["Stuart Stock <stuart@int08h.com>", "Aaron Hill <aa1ronham@gmail.com>"]
 license = "Apache-2.0"
@@ -33,8 +33,8 @@ chrono = "0.4"
 hex = "0.3"
 base64 = "0.9"
 
-rusoto_core = { version = "0.34", optional = true }
-rusoto_kms = { version = "0.34", optional = true }
+rusoto_core = { version = "0.36", optional = true }
+rusoto_kms = { version = "0.36", optional = true }
 
 # google-cloudkms1 intentionally uses an old version of Hyper. See
 # https://github.com/Byron/google-apis-rs/issues/173 for more information.
diff --git a/src/bin/roughenough-server.rs b/src/bin/roughenough-server.rs
index 5f70da0..88c8e83 100644
--- a/src/bin/roughenough-server.rs
+++ b/src/bin/roughenough-server.rs
@@ -32,6 +32,8 @@ use roughenough::config::ServerConfig;
 use roughenough::roughenough_version;
 use roughenough::server::Server;
 
+use mio::Events;
+
 macro_rules! check_ctrlc {
     ($keep_running:expr) => {
         if !$keep_running.load(Ordering::Acquire) {
@@ -74,9 +76,11 @@ fn polling_loop(config: Box<ServerConfig>) {
     ctrlc::set_handler(move || kr.store(false, Ordering::Release))
         .expect("failed setting Ctrl-C handler");
 
+    let mut events = Events::with_capacity(64);
+
     loop {
         check_ctrlc!(kr_new);
-        if server.process_events() {
+        if server.process_events(&mut events) {
             return;
         }
     }
diff --git a/src/config/mod.rs b/src/config/mod.rs
index 65204e6..fb7854f 100644
--- a/src/config/mod.rs
+++ b/src/config/mod.rs
@@ -112,7 +112,7 @@ pub trait ServerConfig {
 ///   * `ENV` will return an [`EnvironmentConfig`](struct.EnvironmentConfig.html)
 ///   * any other value returns a [`FileConfig`](struct.FileConfig.html)
 ///
-pub fn make_config(arg: &str) -> Result<Box<ServerConfig>, Error> {
+pub fn make_config(arg: &str) -> Result<Box<dyn ServerConfig>, Error> {
     if arg == "ENV" {
         match EnvironmentConfig::new() {
             Ok(cfg) => Ok(Box::new(cfg)),
@@ -129,7 +129,7 @@ pub fn make_config(arg: &str) -> Result<Box<ServerConfig>, Error> {
 ///
 /// Validate configuration settings. Returns `true` if the config is valid, `false` otherwise.
 ///
-pub fn is_valid_config(cfg: &Box<ServerConfig>) -> bool {
+pub fn is_valid_config(cfg: &Box<dyn ServerConfig>) -> bool {
     let mut is_valid = true;
 
     if cfg.port() == 0 {
diff --git a/src/lib.rs b/src/lib.rs
index 4ad6390..6e7a88a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -74,7 +74,7 @@ pub use crate::message::RtMessage;
 pub use crate::tag::Tag;
 
 /// Version of Roughenough
-pub const VERSION: &str = "1.1.1";
+pub const VERSION: &str = "1.1.2";
 
 /// Roughenough version string enriched with any compile-time optional features
 pub fn roughenough_version() -> String {
diff --git a/src/server.rs b/src/server.rs
index 01bbef6..87a4a72 100644
--- a/src/server.rs
+++ b/src/server.rs
@@ -23,20 +23,20 @@ use std::process;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Arc;
 use std::time::Duration;
+use std::io::Write;
 use time;
 
 use byteorder::{LittleEndian, WriteBytesExt};
 
 use mio::net::{TcpListener, UdpSocket};
 use mio::{Events, Poll, PollOpt, Ready, Token};
+use mio::tcp::Shutdown;
 use mio_extras::timer::Timer;
 
 use crate::config::ServerConfig;
 use crate::key::{LongTermKey, OnlineKey};
 use crate::kms;
 use crate::merkle::MerkleTree;
-use mio::tcp::Shutdown;
-use std::io::Write;
 use crate::{Error, RtMessage, Tag, MIN_REQUEST_LENGTH};
 
 macro_rules! check_ctrlc {
@@ -67,7 +67,7 @@ const HTTP_RESPONSE: &str = "HTTP/1.1 200 OK\nContent-Length: 0\nConnection: clo
 /// See [the config module](../config/index.html) for more information.
 ///
 pub struct Server {
-    config: Box<ServerConfig>,
+    config: Box<dyn ServerConfig>,
     online_key: OnlineKey,
     cert_bytes: Vec<u8>,
 
@@ -80,7 +80,6 @@ pub struct Server {
     poll_duration: Option<Duration>,
     timer: Timer<()>,
     poll: Poll,
-    events: Events,
     merkle: MerkleTree,
     requests: Vec<(Vec<u8>, SocketAddr)>,
     buf: [u8; 65_536],
@@ -164,7 +163,6 @@ impl Server {
             poll_duration,
             timer,
             poll,
-            events: Events::with_capacity(32),
             merkle,
             requests,
             buf: [0u8; 65_536],
@@ -176,147 +174,64 @@ impl Server {
         }
     }
 
-    /// Returns a reference counted pointer the this server's `keep_running` value.
-    pub fn get_keep_running(&self) -> Arc<AtomicBool> {
-        self.keep_running.clone()
+    /// Returns a reference to the server's long-term public key
+    pub fn get_public_key(&self) -> &str {
+        &self.public_key
     }
 
-    // extract the client's nonce from its request
-    fn nonce_from_request<'a>(&self, buf: &'a [u8], num_bytes: usize) -> Result<&'a [u8], Error> {
-        if num_bytes < MIN_REQUEST_LENGTH as usize {
-            return Err(Error::RequestTooShort);
-        }
-
-        let tag_count = &buf[..4];
-        let expected_nonc = &buf[8..12];
-        let expected_pad = &buf[12..16];
-
-        let tag_count_is_2 = tag_count == [0x02, 0x00, 0x00, 0x00];
-        let tag1_is_nonc = expected_nonc == Tag::NONC.wire_value();
-        let tag2_is_pad = expected_pad == Tag::PAD.wire_value();
-
-        if tag_count_is_2 && tag1_is_nonc && tag2_is_pad {
-            Ok(&buf[0x10..0x50])
-        } else {
-            Err(Error::InvalidRequest)
-        }
+    /// Returns a reference to the server's on-line (delegated) key
+    pub fn get_online_key(&self) -> &OnlineKey {
+        &self.online_key
     }
 
-    fn make_response(
-        &self,
-        srep: &RtMessage,
-        cert_bytes: &[u8],
-        path: &[u8],
-        idx: u32,
-    ) -> RtMessage {
-        let mut index = [0; 4];
-        (&mut index as &mut [u8])
-            .write_u32::<LittleEndian>(idx)
-            .unwrap();
-
-        let sig_bytes = srep.get_field(Tag::SIG).unwrap();
-        let srep_bytes = srep.get_field(Tag::SREP).unwrap();
+    /// Returns a reference to the `ServerConfig` this server was configured with
+    pub fn get_config(&self) -> &Box<dyn ServerConfig> {
+        &self.config
+    }
 
-        let mut response = RtMessage::new(5);
-        response.add_field(Tag::SIG, sig_bytes).unwrap();
-        response.add_field(Tag::PATH, path).unwrap();
-        response.add_field(Tag::SREP, srep_bytes).unwrap();
-        response.add_field(Tag::CERT, cert_bytes).unwrap();
-        response.add_field(Tag::INDX, &index).unwrap();
+    /// Returns a reference counted pointer the this server's `keep_running` value.
+    pub fn get_keep_running(&self) -> Arc<AtomicBool> {
+        self.keep_running.clone()
+    }
 
-        response
+    #[cfg(fuzzing)]
+    pub fn send_to_self(&mut self, data: &[u8]) {
+        self.response_counter = 0;
+        self.num_bad_requests = 0;
+        let res = self
+            .fake_client_socket
+            .send_to(data, &self.socket.local_addr().unwrap());
+        info!("Sent to self: {:?}", res);
     }
 
     /// The main processing function for incoming connections. This method should be
     /// called repeatedly in a loop to process requests. It returns 'true' when the
     /// server has shutdown (due to keep_running being set to 'false').
     ///
-    pub fn process_events(&mut self) -> bool {
+    pub fn process_events(&mut self, events: &mut Events) -> bool {
         self.poll
-            .poll(&mut self.events, self.poll_duration)
+            .poll(events, self.poll_duration)
             .expect("poll failed");
 
-        for event in self.events.iter() {
-            match event.token() {
+        for msg in events.iter() {
+            match msg.token() {
                 MESSAGE => {
-                    let mut done = false;
-
-                    'process_batch: loop {
+                    loop {
                         check_ctrlc!(self.keep_running);
 
-                        let resp_start = self.response_counter;
-
-                        for i in 0..self.config.batch_size() {
-                            match self.socket.recv_from(&mut self.buf) {
-                                Ok((num_bytes, src_addr)) => {
-                                    match self.nonce_from_request(&self.buf, num_bytes) {
-                                        Ok(nonce) => {
-                                            self.requests.push((Vec::from(nonce), src_addr));
-                                            self.merkle.push_leaf(nonce);
-                                        }
-                                        Err(e) => {
-                                            self.num_bad_requests += 1;
-
-                                            info!(
-                                                "Invalid request: '{:?}' ({} bytes) from {} (#{} in batch, resp #{})",
-                                                e, num_bytes, src_addr, i, resp_start + i as u64
-                                            );
-                                        }
-                                    }
-                                }
-                                Err(e) => match e.kind() {
-                                    ErrorKind::WouldBlock => {
-                                        done = true;
-                                        break;
-                                    }
-                                    _ => {
-                                        error!(
-                                            "Error receiving from socket: {:?}: {:?}",
-                                            e.kind(),
-                                            e
-                                        );
-                                        break;
-                                    }
-                                },
-                            };
-                        }
-
-                        if self.requests.is_empty() {
-                            break 'process_batch;
-                        }
-
-                        let merkle_root = self.merkle.compute_root();
-                        let srep = self.online_key.make_srep(time::get_time(), &merkle_root);
-
-                        for (i, &(ref nonce, ref src_addr)) in self.requests.iter().enumerate() {
-                            let paths = self.merkle.get_paths(i);
-
-                            let resp =
-                                self.make_response(&srep, &self.cert_bytes, &paths, i as u32);
-                            let resp_bytes = resp.encode().unwrap();
-
-                            let bytes_sent = self
-                                .socket
-                                .send_to(&resp_bytes, &src_addr)
-                                .expect("send_to failed");
+                        self.merkle.reset();
+                        self.requests.clear();
 
-                            self.response_counter += 1;
+                        let socket_now_empty = self.collect_requests();
 
-                            info!(
-                                "Responded {} bytes to {} for '{}..' (#{} in batch, resp #{})",
-                                bytes_sent,
-                                src_addr,
-                                hex::encode(&nonce[0..4]),
-                                i,
-                                self.response_counter
-                            );
+                        if self.requests.is_empty() {
+                            break;
                         }
 
-                        self.merkle.reset();
-                        self.requests.clear();
+                        self.send_responses();
 
-                        if done {
-                            break 'process_batch;
+                        if socket_now_empty {
+                            break;
                         }
                     }
                 }
@@ -362,28 +277,108 @@ impl Server {
         false
     }
 
-    /// Returns a reference to the server's long-term public key
-    pub fn get_public_key(&self) -> &str {
-        &self.public_key
+    // Read and process client requests from socket until empty or 'batch_size' number of
+    // requests have been read.
+    fn collect_requests(&mut self) -> bool {
+        for i in 0..self.config.batch_size() {
+            match self.socket.recv_from(&mut self.buf) {
+                Ok((num_bytes, src_addr)) => {
+                    match self.nonce_from_request(&self.buf, num_bytes) {
+                        Ok(nonce) => {
+                            self.requests.push((Vec::from(nonce), src_addr));
+                            self.merkle.push_leaf(nonce);
+                        }
+                        Err(e) => {
+                            self.num_bad_requests += 1;
+
+                            info!(
+                                "Invalid request: '{:?}' ({} bytes) from {} (#{} in batch, resp #{})",
+                                e, num_bytes, src_addr, i, self.response_counter + i as u64
+                            );
+                        }
+                    }
+                }
+                Err(e) => match e.kind() {
+                    ErrorKind::WouldBlock => {
+                        return true;
+                    }
+                    _ => {
+                        error!("Error receiving from socket: {:?}: {:?}", e.kind(), e);
+                        return false;
+                    }
+                },
+            };
+        }
+
+        false
     }
 
-    /// Returns a reference to the server's on-line (delegated) key
-    pub fn get_online_key(&self) -> &OnlineKey {
-        &self.online_key
+    // extract the client's nonce from its request
+    fn nonce_from_request<'a>(&self, buf: &'a [u8], num_bytes: usize) -> Result<&'a [u8], Error> {
+        if num_bytes < MIN_REQUEST_LENGTH as usize {
+            return Err(Error::RequestTooShort);
+        }
+
+        let tag_count = &buf[..4];
+        let expected_nonc = &buf[8..12];
+        let expected_pad = &buf[12..16];
+
+        let tag_count_is_2 = tag_count == [0x02, 0x00, 0x00, 0x00];
+        let tag1_is_nonc = expected_nonc == Tag::NONC.wire_value();
+        let tag2_is_pad = expected_pad == Tag::PAD.wire_value();
+
+        if tag_count_is_2 && tag1_is_nonc && tag2_is_pad {
+            Ok(&buf[0x10..0x50])
+        } else {
+            Err(Error::InvalidRequest)
+        }
     }
 
-    /// Returns a reference to the `ServerConfig` this server was configured with
-    pub fn get_config(&self) -> &Box<ServerConfig> {
-        &self.config
+    fn send_responses(&mut self) -> () {
+        let merkle_root = self.merkle.compute_root();
+
+        // The SREP tag is identical for each response
+        let srep = self.online_key.make_srep(time::get_time(), &merkle_root);
+
+        for (i, &(ref nonce, ref src_addr)) in self.requests.iter().enumerate() {
+            let paths = self.merkle.get_paths(i);
+            let resp = self.make_response(&srep, &self.cert_bytes, &paths, i as u32);
+            let resp_bytes = resp.encode().unwrap();
+
+            let bytes_sent = self
+                .socket
+                .send_to(&resp_bytes, &src_addr)
+                .expect("send_to failed");
+
+            self.response_counter += 1;
+
+            info!(
+                "Responded {} bytes to {} for '{}..' (#{} in batch, resp #{})",
+                bytes_sent,
+                src_addr,
+                hex::encode(&nonce[0..4]),
+                i,
+                self.response_counter
+            );
+        }
     }
 
-    #[cfg(fuzzing)]
-    pub fn send_to_self(&mut self, data: &[u8]) {
-        self.response_counter = 0;
-        self.num_bad_requests = 0;
-        let res = self
-            .fake_client_socket
-            .send_to(data, &self.socket.local_addr().unwrap());
-        info!("Sent to self: {:?}", res);
+    fn make_response(&self, srep: &RtMessage, cert_bytes: &[u8], path: &[u8], idx: u32) -> RtMessage {
+        let mut index = [0; 4];
+        (&mut index as &mut [u8])
+            .write_u32::<LittleEndian>(idx)
+            .unwrap();
+
+        let sig_bytes = srep.get_field(Tag::SIG).unwrap();
+        let srep_bytes = srep.get_field(Tag::SREP).unwrap();
+
+        let mut response = RtMessage::new(5);
+        response.add_field(Tag::SIG, sig_bytes).unwrap();
+        response.add_field(Tag::PATH, path).unwrap();
+        response.add_field(Tag::SREP, srep_bytes).unwrap();
+        response.add_field(Tag::CERT, cert_bytes).unwrap();
+        response.add_field(Tag::INDX, &index).unwrap();
+
+        response
     }
 }