commit ee855447c61b6a8703c33cd0421ff2e20efb52e5 Author: Gitea Date: Thu Jul 14 17:48:59 2022 +0300 Initial commit; can send and receive basic text diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..ea8c4bf --- /dev/null +++ b/.gitignore @@ -0,0 +1 @@ +/target diff --git a/COPYING b/COPYING new file mode 100644 index 0000000..be3f7b2 --- /dev/null +++ b/COPYING @@ -0,0 +1,661 @@ + GNU AFFERO GENERAL PUBLIC LICENSE + Version 3, 19 November 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU Affero General Public License is a free, copyleft license for +software and other kinds of works, specifically designed to ensure +cooperation with the community in the case of network server software. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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There are many ways you could offer source, and different +solutions will be better for different programs; see section 13 for the +specific requirements. + + You should also get your employer (if you work as a programmer) or school, +if any, to sign a "copyright disclaimer" for the program, if necessary. +For more information on this, and how to apply and follow the GNU AGPL, see +. diff --git a/Cargo.lock b/Cargo.lock new file mode 100644 index 0000000..c23c77b --- /dev/null +++ b/Cargo.lock @@ -0,0 +1,7 @@ +# This file is automatically @generated by Cargo. +# It is not intended for manual editing. +version = 3 + +[[package]] +name = "ddtu" +version = "0.1.0" diff --git a/Cargo.toml b/Cargo.toml new file mode 100644 index 0000000..4771c57 --- /dev/null +++ b/Cargo.toml @@ -0,0 +1,8 @@ +[package] +name = "ddtu" +version = "0.1.0" +edition = "2021" + +# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html + +[dependencies] diff --git a/README.md b/README.md new file mode 100644 index 0000000..24da993 --- /dev/null +++ b/README.md @@ -0,0 +1,2 @@ +# ddtu - digital data transferring utility +### Transfer one thing from __here__ to __there__ via the Internet connection \ No newline at end of file diff --git a/TODO b/TODO new file mode 100644 index 0000000..8ec32c6 --- /dev/null +++ b/TODO @@ -0,0 +1,4 @@ +1. Write base foundation for sending and receiving information +2. Wire it all together +3. Make it encrypted +4. Daemon \ No newline at end of file diff --git a/src/args.rs b/src/args.rs new file mode 100644 index 0000000..dcb5801 --- /dev/null +++ b/src/args.rs @@ -0,0 +1,161 @@ +/* +ddtu - digital data transferring utility +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU Affero General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU Affero General Public License for more details. +*/ + +use super::error::Error; +use std::path; + +#[derive(PartialEq, Eq, Debug)] +pub enum RunMode { + SEND, + RECEIVE, + SYNC, + DAEMON, +} + +#[derive(PartialEq, Eq, Debug)] +pub enum Type { + TEXT, + FILE, + DIR, +} + +#[derive(Debug)] +pub struct Args { + pub help: bool, + pub version: bool, + pub mode: RunMode, + pub send_type: Type, + pub address_str: String, + pub send_path: path::PathBuf, + pub save_directory: path::PathBuf, + pub sync_directory: path::PathBuf, + pub text_to_send: String, +} + +impl Args { + pub fn default() -> Args { + return Args{ + help: false, + version: false, + mode: RunMode::DAEMON, + send_type: Type::TEXT, + address_str: "".to_string(), + send_path: path::PathBuf::new(), + save_directory: path::PathBuf::new(), + sync_directory: path::PathBuf::new(), + text_to_send: "".to_string(), + }; + } +} + +pub fn parse(raw_args: &Vec) -> Result { + let mut parsed_args: Args = Args::default(); + + // parse arguments, ignoring the first argument + let arg_amount: usize = raw_args.len(); + if arg_amount < 2 { + return Err(Error::new("no arguments")); + } + + match raw_args[1].to_lowercase().as_str() { + "help" => { + parsed_args.help = true; + } + + "version" => { + parsed_args.version = true; + } + + "send" => { + if arg_amount < 4 { + // not enough arguments ! + return Err(Error::new("not enough arguments for send mode")); + } + + parsed_args.mode = RunMode::SEND; + + // type + match raw_args[2].to_lowercase().as_str() { + "text" => { + parsed_args.send_type = Type::TEXT; + parsed_args.text_to_send = String::from(&raw_args[3]); + } + + "file" => { + parsed_args.send_type = Type::FILE; + parsed_args.send_path = std::path::Path::new(&raw_args[3]).to_path_buf(); + } + + "dir" => { + parsed_args.send_type = Type::DIR; + parsed_args.send_path = std::path::Path::new(&raw_args[3]).to_path_buf(); + } + + _ => { + return Err(Error::new(format!("invalid type {}", raw_args[2]).as_str())); + } + } + + // src + if parsed_args.send_type == Type::FILE || parsed_args.send_type == Type::DIR { + // check if exists + match path::Path::new(raw_args[3].as_str()).exists() { + true => { + parsed_args.send_path = path::Path::new(raw_args[3].as_str()).to_path_buf(); + } + + false => { + return Err(Error::new(format!("\"{}\" does not exist or unreachable", raw_args[3]).as_str())); + } + } + } + } + + "recv" => { + if arg_amount < 3 { + // not enough arguments ! + return Err(Error::new("not enough arguments for receiving mode")); + } + + parsed_args.mode = RunMode::RECEIVE; + parsed_args.address_str = raw_args[2].to_string(); + if arg_amount > 3 { + parsed_args.save_directory = path::Path::new(raw_args[3].as_str()).to_path_buf(); + } + } + + "sync" => { + parsed_args.mode = RunMode::SYNC; + if arg_amount < 3 { + return Err(Error::new("not enough arguments for syncing")); + } + + let sync_path: &path::Path = path::Path::new(raw_args[2].as_str()); + if !sync_path.exists() || !sync_path.is_dir() { + return Err(Error::new(format!("{} does not exist or is not a directory", sync_path.display()).as_str())); + } + } + + "daemon" => { + parsed_args.mode = RunMode::DAEMON; + } + + _ => { + return Err(Error::new(format!("invalid argument {}", raw_args[1]).as_str())); + } + } + + return Ok(parsed_args); +} \ No newline at end of file diff --git a/src/error.rs b/src/error.rs new file mode 100644 index 0000000..ae657b5 --- /dev/null +++ b/src/error.rs @@ -0,0 +1,26 @@ +/* +ddtu - digital data transferring utility +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU Affero General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU Affero General Public License for more details. +*/ + +pub struct Error { + pub text: String, +} + +impl Error { + pub fn new(txt: &str) -> Error { + return Error{ + text: txt.to_string(), + }; + } +} \ No newline at end of file diff --git a/src/main.rs b/src/main.rs new file mode 100644 index 0000000..42cf1c1 --- /dev/null +++ b/src/main.rs @@ -0,0 +1,170 @@ +/* +ddtu - digital data transferring utility +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU Affero General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU Affero General Public License for more details. +*/ + +mod args; +mod error; +mod protocol; + +use args::{Args, RunMode}; +use std::net; +use protocol::Packet; +use protocol::TextPacket; +use protocol::PacketType; + +const VERSION: &str = "v0.1.0"; +const HELP_MESSAGE: &str = +"ddtu - digital data transferring tool v0.1.0 +Usage: +ddtu [FLAG] [MODE] [MODE-specific arguments] + +[FLAG] +[help]: ddtu help -> print help message +[version]: ddtu version -> print version + +[MODE] +[send]: ddtu send [TYPE] [SRC] -> prepare to send [SRC] of [TYPE] and wait for someone to receive +[recv]: ddtu recv [SRC] [DEST](optional) -> receive anything from another ddtu instance running on [SRC], saving it at [DEST] +[sync]: ddtu sync [DIR] [DEST] -> sync [DIRectory] contents with another ddtu instance on [DEST] +[daemon]: ddtu daemon -> start syncing daemon + +[TYPE] +[text]: ddtu send text \'text to send\' -> send text +[file]: ddtu send file \'/home/user/documents/doc.txt\' -> send file doc.txt +[dir]: ddtu send dir \'/home/user/homework\' -> send whole directory recursively + +(c) Kasyanov Nikolay Alexeyevich (Unbewohnte) +"; + + +fn main() { + // get and parse arguments + let raw_args: Vec = std::env::args().collect(); + let args: Args; + + match args::parse(&raw_args) { + Ok(parsed_args) => { + args = parsed_args; + } + + Err(error) => { + println!("error parsing arguments: {}", error.text); + return; + } + } + + println!("{:?}", args); + + // handle them + if args.help { + println!("{}", HELP_MESSAGE); + return; + } + + if args.version { + println!("ddtu {}", VERSION); + return; + } + + match args.mode { + RunMode::RECEIVE => { + let mut conn: net::TcpStream; + match net::TcpStream::connect(&args.address_str) { + Ok(c) => { + conn = c; + } + + Err(error) => { + println!("could not connect to {}: {}", args.address_str, error); + return; + } + } + + println!("connected to {}", args.address_str); + + match protocol::read_next_packet(&mut conn) { + Ok(packet) => { + match packet.get_type() { + PacketType::TextData => { + let mut text_packet = protocol::TextPacket::empty(); + text_packet.from_bytes(packet.as_bytes()); + println!("{}", text_packet.text); + } + + _ => { + + } + } + } + + Err(error) => { + println!("error reading packet: {}", error.text); + } + } + } + + RunMode::SEND => { + let listener: net::TcpListener; + match net::TcpListener::bind("0.0.0.0:10555") { + Ok(l) => { + listener = l; + } + + Err(error) => { + println!("error creating a listener: {}", error); + return; + } + } + + let mut conn: net::TcpStream; + let addr: net::SocketAddr; + match listener.accept() { + Ok((c, a)) => { + conn = c; + addr = a; + } + + Err(error) => { + println!("error establising a new connection: {}", error); + return; + } + } + + println!("{} has connected", addr); + + // send text + let textpacket = TextPacket::new(&args.text_to_send); + match protocol::send_packet(&mut conn, &textpacket) { + Ok(()) => {} + Err(error) => { + println!("{}", error.text); + } + } + + match conn.shutdown(net::Shutdown::Both) { + Ok(()) => {} + Err(error) => { + println!("could not shutdown the connection: {}", error); + return; + } + } + } + + RunMode::DAEMON => { + } + + RunMode::SYNC => { + } + } +} diff --git a/src/protocol.rs b/src/protocol.rs new file mode 100644 index 0000000..484a8fd --- /dev/null +++ b/src/protocol.rs @@ -0,0 +1,391 @@ +/* +ddtu - digital data transferring utility +Copyright (C) 2022 Kasyanov Nikolay Alexeyevich (Unbewohnte) + +This program is free software: you can redistribute it and/or modify +it under the terms of the GNU Affero General Public License as published by +the Free Software Foundation, either version 3 of the License, or +(at your option) any later version. + +This program is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU Affero General Public License for more details. +*/ + +use super::error::Error; +use std::net; +use std::io::Write; +use std::io::Read; + +/* +---PROTOCOL SPECs--- + +- Packet bytes representation - + +First 16 bytes - the total packet length +The next 1 byte - number that represents this packet's type (ID) where: +1: CONNECTION SHUTDOWN PACKET +2: TEXT PACKET +3: FILEINFO PACKET +4: FILEDATA PACKET + +Then the internal structure varies from one packet type to the other, +but the content-types are encoded as follows: +u8 - just 1 BE byte +u128 - 16 BE bytes +String - u128 representing the string length and then UTF-8 encoded character bytes +[u8] - u128 as the length of a byte array, then the array itself +*/ + +fn read_u128(buf: Vec) -> u128 { + let mut arr: [u8; 16] = [0; 16]; + for i in 0..16 { + arr[i] = buf[i]; + } + return u128::from_be_bytes(arr); +} + +fn read_u128_slice(buf_16: &[u8]) -> u128 { + let mut arr: [u8; 16] = [0; 16]; + for i in 0..16 { + arr[i] = buf_16[i]; + } + return u128::from_be_bytes(arr); +} + +fn read_utf8_string(buf: Vec) -> String { + return String::from_utf8_lossy(&buf).into_owned(); +} + +fn read_utf8_string_slice(buf: &[u8]) -> String { + return String::from_utf8_lossy(&buf).into_owned(); +} + + +const CONNECTION_SHUTDOWN_PACKET_ID: u8 = 1; +const TEXT_PACKET_ID: u8 = 2; +const FILEINFO_PACKET_ID: u8 = 3; +const FILEDATA_PACKET_ID: u8 = 4; + +const CHUNK_SIZE: usize = 262_144; // 256 KB + + +#[derive(PartialEq, Eq)] +pub enum PacketType { + ConnectionShutdown, + TextData, + FileInfo, + FileData, +} + +pub trait Packet { + fn get_type(&self) -> PacketType; + fn as_bytes(&self) -> Vec; + fn from_bytes(&mut self, packet_bytes: Vec) -> Option; +} + +pub struct ConnectionShutdownPacket {} + +impl Packet for ConnectionShutdownPacket { + fn get_type(&self) -> PacketType { + return PacketType::ConnectionShutdown; + } + + fn as_bytes(&self) -> Vec { + return vec!(CONNECTION_SHUTDOWN_PACKET_ID.to_be_bytes()[0]); + } + + fn from_bytes(&mut self, _packet_bytes: Vec) -> Option { + return None; + } +} + +pub struct TextPacket { + pub text: String, +} + +impl TextPacket { + pub fn empty() -> TextPacket { + return TextPacket{ + text: "".to_string(), + }; + } + + pub fn new(txt: &str) -> TextPacket { + return TextPacket { + text: txt.to_string(), + } + } +} + +impl Packet for TextPacket { + fn get_type(&self) -> PacketType { + return PacketType::TextData; + } + + fn as_bytes(&self) -> Vec { + let mut packet_as_bytes: Vec = Vec::::new(); + + packet_as_bytes.extend_from_slice(&TEXT_PACKET_ID.to_be_bytes()); + + let text_length: u128 = self.text.len() as u128; + packet_as_bytes.extend_from_slice(&text_length.to_be_bytes()); + packet_as_bytes.extend_from_slice(&self.text.as_bytes()); + + return packet_as_bytes; + } + + fn from_bytes(&mut self, packet_bytes: Vec) -> Option { + if packet_bytes.len() < 18 { + return Some( + Error::new(format!("{} bytes is too small for a text packet to be valid", packet_bytes.len()).as_str() + )); + } + + // retrieve and check for packet type byte + match packet_bytes[0].to_be() { + TEXT_PACKET_ID => {} + _ => { + return Some(Error::new("packet type is not of a text packet")); + } + } + + // get text length + let text_length: u128 = read_u128_slice(&packet_bytes[1..17]); + + if text_length as usize > packet_bytes[17..].len() { + return Some( + Error::new( + format!( + "text length ({}) is bigger than provided packet bytes length ({})", + text_length, + packet_bytes[16..].len() + ).as_str() + ) + ); + } + + // extract text + self.text = read_utf8_string_slice(&packet_bytes[17..]); + + return None; + } +} + +pub struct FileinfoPacket { + pub file_id: u128, + pub filename: String, + pub filesize: u128, + pub relative_path: String, +} + +impl FileinfoPacket { + pub fn empty() -> FileinfoPacket { + return FileinfoPacket{ + file_id: 0, + filename: "".to_string(), + filesize: 0, + relative_path: "".to_string(), + }; + } +} + +impl Packet for FileinfoPacket { + fn get_type(&self) -> PacketType { + return PacketType::FileInfo; + } + + fn as_bytes(&self) -> Vec { + let mut packet_as_bytes: Vec = Vec::::new(); + + // file id + packet_as_bytes.extend_from_slice(&self.file_id.to_be_bytes()); + + // filename + let filename_bytes_length: u128 = self.filename.len() as u128; + packet_as_bytes.extend_from_slice(&filename_bytes_length.to_be_bytes()); + packet_as_bytes.extend_from_slice(&self.filename.as_bytes()); + + // filesize + packet_as_bytes.extend_from_slice(&self.filesize.to_be_bytes()); + + // relative path + let relative_path_bytes_length: u128 = self.relative_path.len() as u128; + packet_as_bytes.extend_from_slice(&relative_path_bytes_length.to_be_bytes()); + packet_as_bytes.extend_from_slice(&self.relative_path.as_bytes()); + + return packet_as_bytes; + } + + fn from_bytes(&mut self, packet_bytes: Vec) -> Option { + // file id + self.file_id = read_u128_slice(&packet_bytes[0..16]); + + // get filename + let filename_length: u128 = read_u128_slice(&packet_bytes[16..32]); + self.filename = read_utf8_string_slice(&packet_bytes[32..(filename_length+32) as usize]); + + // filesize + self.filesize = read_u128_slice(&packet_bytes[(filename_length+32) as usize..(filename_length+32+16) as usize]); + + // relative path + let rel_path_length: u128 = read_u128_slice( + &packet_bytes[(filename_length+32+16) as usize..(filename_length+32+16+16)as usize] + ); + self.relative_path = read_utf8_string_slice( + &packet_bytes[(filename_length+32+16+16) as usize..(filename_length+32+16+16+rel_path_length) as usize] + ); + + return None; + } +} + +pub struct FileDataPacket { + pub file_id: u128, + pub chunk_no: u128, + pub chunk: [u8; CHUNK_SIZE], +} + +impl FileDataPacket { + pub fn empty() -> FileDataPacket { + return FileDataPacket { + file_id: 0, + chunk_no: 0, + chunk: [0; CHUNK_SIZE], + } + } +} + +impl Packet for FileDataPacket { + fn get_type(&self) -> PacketType { + return PacketType::FileData; + } + + fn as_bytes(&self) -> Vec { + let packet_bytes: Vec = Vec::::new(); + return packet_bytes; + } + + fn from_bytes(&mut self, packet_bytes: Vec) -> Option { + return None; + } +} + + +pub fn send_packet(conn: &mut net::TcpStream, packet: &dyn Packet) -> Result<(), Error> { + let mut payload: Vec = Vec::::new(); + + let packet_bytes: Vec = packet.as_bytes(); + let packet_len: usize = packet_bytes.len(); + + payload.extend_from_slice(&u128::to_be_bytes(packet_len as u128)); + payload.extend_from_slice(&packet_bytes); + + match conn.write_all(&payload) { + Ok(()) => { + return Ok(()); + } + + Err(error) => { + return Err(Error::new(format!("could not write packet to the connection: {}", error).as_str())) + } + } +} + +pub fn read_next_packet(conn: &mut net::TcpStream) -> Result, Error> { + let mut u128_buf: [u8; 16] = [0; 16]; + + match conn.read_exact(&mut u128_buf) { + Ok(()) => {} + // Ok(read_bytes) => { + // if read_bytes != 16 { + // return Err(Error::new(format!("read {} initial length bytes instead of 16", read_bytes).as_str())); + // } + // } + Err(error) => { + return Err(Error::new(format!("error while reading initial length bytes: {}", error).as_str())); + } + } + let packet_len: u128 = u128::from_be_bytes(u128_buf); + + let mut packet_bytes = vec!(0; packet_len as usize); + // let mut packet_bytes: Vec = Vec::with_capacity(packet_len as usize); + match conn.read_exact(&mut packet_bytes) { + Ok(()) => {} + // Ok(read_bytes) => { + // if read_bytes != packet_len { + // return Err( + // Error::new( + // format!("read {} bytes of packet contents instead of specified {}", + // read_bytes, + // packet_len).as_str() + // ) + // ); + // } + // } + Err(error) => { + return Err(Error::new(format!("error while reading packet contents: {}", error).as_str())); + } + } + + if packet_bytes.len() < packet_len as usize { + return Err( + Error::new( + format!("read {} packet bytes instead of specified {}", packet_bytes.len(), packet_len).as_str()) + ); + } + + let packet_type_byte: u8 = u8::from_be_bytes([packet_bytes[0]]); + match packet_type_byte { + CONNECTION_SHUTDOWN_PACKET_ID => { + return Ok(Box::new(ConnectionShutdownPacket{})); + } + + TEXT_PACKET_ID => { + let mut new_text_packet: TextPacket = TextPacket::empty(); + let result = new_text_packet.from_bytes(packet_bytes); + match result { + Some(error) => { + return Err(Error::new(format!("could not construct new text packet: {}", error.text).as_str())); + } + + None => { + return Ok(Box::new(new_text_packet)); + } + } + } + + FILEINFO_PACKET_ID => { + let mut new_fileinfo_packet: FileinfoPacket = FileinfoPacket::empty(); + let result = new_fileinfo_packet.from_bytes(packet_bytes); + match result { + Some(error) => { + return Err(Error::new(format!("could not construct new fileinfo packet: {}", error.text).as_str())); + } + + None => { + return Ok(Box::new(new_fileinfo_packet)); + } + } + } + + FILEDATA_PACKET_ID => { + let mut new_filedata_packet: FileDataPacket = FileDataPacket::empty(); + let result = new_filedata_packet.from_bytes(packet_bytes); + match result { + Some(error) => { + return Err(Error::new(format!("could not construct new filedata packet: {}", error.text).as_str())); + } + + None => { + return Ok(Box::new(new_filedata_packet)); + } + } + } + + _ => { + return Err(Error::new(format!("invalid packet type ID \"{}\"", packet_type_byte).as_str())); + } + } +} \ No newline at end of file