Implemented DCC get for downloading files.

Does not yet support sending files.
Closes osa1#206

Added connection timeout

Fixed NOTICE format which was causing an issue. Spawn regular task instead of local for file download.

Only read number of bytes read.

README.md

@@ -195,7 +195,11 @@ Commands start with `/` character.
   Running this command in a server tab applies it to all channels of that
   server. You can check your notify state in the status line.
 
-## Server commands
+- `/dcc [get] <sender> <filename>`: When you receive a DCC SEND message, you can 
+  accept it and download the file with this command. Currently sending files
+  is not supported.
+
+## Server Commands
 
 For commands not supported by tiny as a slash command, sending the command in
 the server tab will send the message directly to the server.

crates/libtiny_client/Cargo.toml

@@ -19,6 +19,6 @@ libtiny_wire = { path = "../libtiny_wire" }
 log = "0.4"
 native-tls = { version = "0.2", optional = true }
 rustls-native-certs = { version = "0.5", optional = true }
-tokio = { version = "0.3.6", default-features = false, features = ["rt", "sync", "stream", "time", "io-util", "net"] }
+tokio = { version = "0.3.6", default-features = false, features = ["rt", "sync", "stream", "time", "io-util", "net", "fs"] }
 tokio-native-tls = { version = "0.2", optional = true }
 tokio-rustls = { version = "0.21", optional = true }

crates/libtiny_client/src/dcc.rs

@@ -0,0 +1,152 @@
+use std::fmt;
+use std::net::{IpAddr, Ipv4Addr, SocketAddr};
+use std::str::FromStr;
+
+#[derive(Debug, PartialEq)]
+pub struct DCCRecord {
+    /// SEND or CHAT (only supporting SEND right now)
+    dcc_type: DCCType,
+    /// IP address and port
+    address: SocketAddr,
+    /// Nickname of person who wants to send
+    origin: String,
+    /// Client nickname
+    receiver: String,
+    /// Argument - filename or string "chat"
+    argument: String,
+    /// File size of file that will be sent in bytes
+    file_size: Option<u32>,
+}
+
+#[derive(Debug, Copy, Clone, PartialEq)]
+pub enum DCCType {
+    SEND,
+    CHAT,
+}
+
+#[derive(Debug)]
+pub struct DCCTypeParseError;
+
+impl std::error::Error for DCCTypeParseError {}
+
+impl fmt::Display for DCCTypeParseError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "DCCType could not be parsed from string.")
+    }
+}
+
+impl FromStr for DCCType {
+    type Err = DCCTypeParseError;
+    fn from_str(input: &str) -> Result<DCCType, DCCTypeParseError> {
+        match input {
+            "SEND" => Ok(DCCType::SEND),
+            "CHAT" => Ok(DCCType::CHAT),
+            _ => Err(DCCTypeParseError),
+        }
+    }
+}
+
+impl fmt::Display for DCCType {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            DCCType::CHAT => write!(f, "CHAT"),
+            DCCType::SEND => write!(f, "SEND"),
+        }
+    }
+}
+
+impl DCCRecord {
+    /// DCC type argument address port [size]
+    ///
+    /// type	 - The connection type.
+    /// argument - The connectin type dependant argument.
+    /// address	 - The host address of the initiator as an integer.
+    /// port	 - The port or the socket on which the initiator expects
+    /// 	       to receive the connection.
+    /// size     - If the connection type is "SEND" (see below), then size
+    /// 	       will indicate the size of the file being offered. Obsolete
+    /// 	       IRCII clients do not send this, so be prepared if this is
+    /// 	       not present.
+
+    /// The following DCC connection types are defined:
+    ///
+    /// Type	Purpose					                Argument
+    /// CHAT	To carry on a semi-secure conversation	the string "chat"
+    /// SEND	To send a file to the recipient		    the file name
+    pub fn from(
+        origin: &str,
+        receiver: &str,
+        msg: &str,
+    ) -> Result<DCCRecord, Box<dyn std::error::Error>> {
+        let mut param_iter: Vec<&str> = msg.split_whitespace().collect();
+        let dcc_type: DCCType = param_iter.remove(0).parse()?;
+        let file_size = param_iter.pop().and_then(|fs| fs.parse::<u32>().ok());
+        let port: u16 = param_iter.pop().unwrap().parse()?;
+
+        let address: u32 = param_iter.pop().unwrap().parse()?;
+        let address_dot_decimal: Ipv4Addr = Ipv4Addr::new(
+            (address >> 24) as u8,
+            (address >> 16) as u8,
+            (address >> 8) as u8,
+            (address) as u8,
+        );
+
+        let socket_address = SocketAddr::new(IpAddr::V4(address_dot_decimal), port);
+
+        let argument = param_iter.join("");
+        let argument = argument.trim_start_matches('"').trim_end_matches('"');
+
+        Ok(DCCRecord {
+            dcc_type,
+            address: socket_address,
+            origin: origin.to_string(),
+            receiver: receiver.to_string(),
+            argument: argument.to_string(),
+            file_size,
+        })
+    }
+
+    pub fn get_type(&self) -> DCCType {
+        self.dcc_type
+    }
+
+    pub fn get_addr(&self) -> &SocketAddr {
+        &self.address
+    }
+
+    pub fn get_argument(&self) -> &String {
+        &self.argument
+    }
+
+    pub fn get_file_size(&self) -> Option<u32> {
+        self.file_size
+    }
+
+    pub fn get_receiver(&self) -> &String {
+        &self.receiver
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn can_parse() {
+        let expected = DCCRecord {
+            dcc_type: DCCType::SEND,
+            address: SocketAddr::new(IpAddr::V4(Ipv4Addr::new(173, 80, 26, 71)), 3078),
+            origin: "Origin".to_string(),
+            receiver: "me".to_string(),
+            argument: "SearchBot_results_for_python.txt.zip".to_string(),
+            file_size: Some(24999),
+        };
+        let s = r#"SEND "SearchBot_results_for_ python.txt.zip" 2907707975 3078 24999"#;
+        let r = DCCRecord::from("Origin", "me", s);
+        assert_eq!(expected, r.unwrap());
+
+        let s = r#"SEND SearchBot_results_for_python.txt.zip 2907707975 3078 24999"#;
+        let r = DCCRecord::from("Origin", "me", s);
+        assert_eq!(expected, r.unwrap());
+    }
+}

crates/libtiny_client/src/lib.rs

@@ -2,11 +2,13 @@
 #![allow(clippy::unneeded_field_pattern)]
 #![allow(clippy::cognitive_complexity)]
 
+mod dcc;
 mod pinger;
 mod state;
 mod stream;
 mod utils;
 
+pub use dcc::DCCType;
 use libtiny_common::{ChanName, ChanNameRef};
 pub use libtiny_wire as wire;
 
@@ -18,9 +20,12 @@ use futures::future::FutureExt;
 use futures::stream::{Fuse, StreamExt};
 use futures::{pin_mut, select};
 use std::net::{SocketAddr, ToSocketAddrs};
+use std::path::PathBuf;
 use std::time::Duration;
+use tokio::fs::OpenOptions;
 use tokio::io::{AsyncReadExt, AsyncWriteExt};
 use tokio::sync::mpsc;
+use tokio::time::timeout;
 
 #[macro_use]
 extern crate log;
@@ -253,6 +258,36 @@ impl Client {
     pub fn get_chan_nicks(&self, chan: &ChanNameRef) -> Vec<String> {
         self.state.get_chan_nicks(chan)
     }
+
+    /// Checks if we have a stored DCCRecord for the provided parameters
+    /// Starts download of file if a record is found.
+    /// Deletes record after download attempt
+    /// Returns boolean if record is found
+    pub fn get_dcc_rec(&mut self, origin: &str, download_dir: PathBuf, file_name: &str) -> bool {
+        let rec = self.state.get_dcc_rec(origin, file_name);
+        if let Some(rec) = rec {
+            debug!("found rec {:?}", rec);
+            dcc_file_get(
+                &mut self.msg_chan,
+                *rec.get_addr(),
+                download_dir,
+                file_name.to_string(),
+                rec.get_receiver().to_string(),
+            );
+            true
+        } else {
+            false
+        }
+    }
+
+    /// Creates a dcc record and returns the argument (filename) and file size if provided
+    pub fn create_dcc_rec(
+        &self,
+        origin: &str,
+        msg: &str,
+    ) -> Option<(dcc::DCCType, String, Option<u32>)> {
+        self.state.add_dcc_rec(origin, msg)
+    }
 }
 
 //
@@ -673,3 +708,127 @@ async fn try_connect(
         }
     }
 }
+
+/// Spawns a task to connect to given address to download
+/// a file
+/// https://www.irchelp.org/protocol/ctcpspec.html
+fn dcc_file_get(
+    msg_chan: &mut mpsc::Sender<Cmd>,
+    addr: SocketAddr,
+    mut download_dir: PathBuf,
+    file_name: String,
+    target: String,
+) {
+    let mut msg_chan = msg_chan.clone();
+    tokio::task::spawn(async move {
+        let stream = match timeout(
+            tokio::time::Duration::from_secs(25),
+            tokio::net::TcpStream::connect(addr),
+        )
+        .await
+        {
+            Err(err) => {
+                error!("{}", err);
+                let err_msg = "File transfer connection timed out.";
+                dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg).await;
+                return;
+            }
+            Ok(stream) => match stream {
+                Err(err) => {
+                    error!("{}", err);
+                    let err_msg = "File transfer connection failed.";
+                    dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg).await;
+                    return;
+                }
+                Ok(stream) => stream,
+            },
+        };
+
+        let (mut rx, mut tx) = tokio::io::split(stream);
+
+        // Try to create the download directory if it isn't there
+        if let Err(err) = tokio::fs::create_dir_all(&download_dir).await {
+            // Directory already exists
+            if err.kind() != tokio::io::ErrorKind::AlreadyExists {
+                error!("{}", err);
+                let err_msg = "Couldn't create download directory.";
+                dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg).await;
+                return;
+            }
+        }
+        // Add the file name to the file path
+        download_dir.push(&file_name);
+        // Create a new file for write inside the download directory
+        let mut file = match OpenOptions::new()
+            .write(true)
+            .create_new(true)
+            .open(download_dir)
+            .await
+        {
+            Err(err) => {
+                error!("{}", err);
+                let err_msg = format!("Couldn't create file: {}.", file_name);
+                dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg.as_str()).await;
+                return;
+            }
+            Ok(file) => file,
+        };
+        // Stores total bytes received
+        let mut bytes_received: u32 = 0;
+        loop {
+            let mut buf: [u8; 1024] = [0; 1024];
+            match rx.read(&mut buf).await {
+                Err(err) => {
+                    error!("{}", err);
+                    let err_msg = "Error reading from socket for dcc.";
+                    dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg).await;
+                    return;
+                }
+                Ok(0) => break,
+                Ok(bytes) => {
+                    bytes_received += bytes as u32;
+                    // Write bytes to file
+                    if let Err(err) = file.write(&buf[..bytes]).await {
+                        error!("{}", err);
+                        let err_msg = "Error writing to file.";
+                        dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg).await;
+                        return;
+                    }
+                    // Send back number of bytes read
+                    let response: [u8; 4] = [
+                        (bytes_received >> 24) as u8,
+                        (bytes_received >> 16) as u8,
+                        (bytes_received >> 8) as u8,
+                        (bytes_received) as u8,
+                    ];
+                    if let Err(err) = tx.write(&response).await {
+                        error!("{}", err);
+                        let err_msg = "Error responding to sender.";
+                        dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg).await;
+                        return;
+                    }
+                }
+            }
+        }
+        // sync file to filesystem
+        if let Err(err) = file.sync_all().await {
+            error!("{}", err);
+            let err_msg = "Error syncing file to disk.";
+            dcc_to_msgchan(&mut msg_chan, target.as_str(), err_msg).await;
+            return;
+        }
+        // Write message to client that file was successfully downloaded
+        let success_msg = format!(
+            "Downloaded file: {} ({1:.2}KB)",
+            file_name,
+            (bytes_received as f32 / 1024 as f32)
+        );
+        dcc_to_msgchan(&mut msg_chan, target.as_str(), success_msg.as_str()).await;
+    });
+}
+
+async fn dcc_to_msgchan(msg_chan: &mut mpsc::Sender<Cmd>, target: &str, msg: &str) {
+    msg_chan
+        .try_send(Cmd::Msg(wire::notice(target, msg)))
+        .unwrap();
+}