A multithreaded FTP server following the RFC959 protocol.
The server require users to authenticate. Below the list of default users; anonymouys does not require a password.
| user | password |
|---|---|
| anonymous | |
| pedro | drops |
| gaetan | qwasar |
New users may be added in the .users config file. Each user entry has a user and password field delimited by a :. Users are separated by a new line(\n) like so
user1:password1
user2:passowrd2
To create users without password set the password to 0
user_without_password:0
My FTP creates a directory .root/ in the same directory as the running binary. Clients only have access to files within .root/ while
the remaining of the server's filesystem remain private and inaccessible. This is reflected in perspective of what the absolute path is between the client and server.
Server absolute path
/home/username/.root/file.jpg
Client absolute path
file.jpg
Clients are unable to CDUP out of the .root directory.
The server has 3 types of log messages: Error(red),Info(blue) and Debug(yellow). The Debug logs are somewhat noisy and they can be turned on or
off by removing/adding the macro #define DEBUG to/from the include/logger.hpp header.
Build
make
Run
./bin/ftp <port-number>
Run server with unit testing
./bin/ftp <port-number> --test
Clean
make clean
The server listens to new connections (accept) as well as to connected sockets control requests in the main thread. This logic is ran in a single thread using a polling system.
Once a request is received from a client, the server will create a Service object and dispatch it to a threadpool. An available thread will then call Service.work() to execute this request.
Note that only the control connection is managed in the main thread. Data connection are always established from a separated thread within the context of a Service.
The program revolves around modifying a Request object that is created when the server first receives a message from
Connection. This Request is then populated with the request info such as the socket fd of the requesting client, data received etc
and is passed on to a Service that, in its turn will parse and route this request to specific controller.
The threadpool will use all the available threads in you system with std::thread::hardware_concurrency. To avoid the CPU usage going out of control, the threadpool implements a simple throttling logic.
As the server goes idle the loop checking for new jobs will get throttled with longer and longer sleep times from 50ms all the way to 500ms.
| Command | Description |
|---|---|
| CDUP | Change to parent directory |
| QUIT | Disconnects from server |
| PASV | Enter passive mode |
| PWD | Print working directory |
| SYST | Get server operating system |
| NOOP | No Operation (used mostly on keepalives) |
| USER | Authenticate username |
| PASS | Authenticate passowrd |
| CWD | Change directory |
| PORT | Specifies an address and port to which the server should connect |
| TYPE | Sets the transfer mode to ASCII or Binary(Image) |
| RETR | Retrives a copy of a file |
| STOU | Stores a file uniquely |
| RNFR | Select the file to rename |
| RNTO | Sets the new filename to rename to |
| DELE | Deletes a file |
| RMD | Removes a directory |
| MKD | Creates a directory |
| LIST | Returns info of a file or directory if specified, else info of the current working directory |
| NLST | Returns a list of filenames in a specified directory |
| STAT | Returns the server status, including the status of the current connection |
| HELP | Display help of an specific command |
| FEAT | Responds with server features |
| ABOR | No support |
| ACCT | No support |
| SMNT | No support |
| STRU | No support |
| MODE | No support |
| REIN | No support |
| APPE | No support |
| SITE | No support |
| ALLO | No support |
| LPRT | No support |
| LPSV | No support |
| REST | No support |
| Reply | Description |
|---|---|
| 100 series | The requested action is being initiated, expect another reply before proceeding with a new command. |
| 110 | Restart marker replay . In this case, the text is exact and not left to the particular implementation; |
| 120 | Service ready in nnn minutes. |
| 125 | Data connection already open; transfer starting. |
| 150 | File status okay; about to open data connection. |
| 200 series | The requested action has been successfully completed. |
| 202 | Command not implemented, superfluous at this site. |
| 211 | System status, or system help reply. |
| 212 | Directory status. |
| 213 | File status. |
| 214 | Help message. Explains how to use the server or the meaning of a particular non-standard command. This reply is useful only to the human user. |
| 215 | NAME system type. Where NAME is an official system name from the registry kept by IANA. |
| 220 | Service ready for new user. |
| 221 | Service closing control connection. |
| 225 | Data connection open; no transfer in progress. |
| 226 | Closing data connection. Requested file action successful (for example, file transfer or file abort). |
| 227 | Entering Passive Mode (h1,h2,h3,h4,p1,p2). |
| 228 | Entering Long Passive Mode (long address, port). |
| 229 | Entering Extended Passive Mode ( |
| 230 | User logged in, proceed. Logged out if appropriate. |
| 231 | User logged out; service terminated. |
| 232 | Logout command noted, will complete when transfer done. |
| 234 | Specifies that the server accepts the authentication mechanism specified by the client, and the exchange of security data is complete. |
| 250 | Requested file action okay, completed. |
| 257 | "PATHNAME" created. |
| 300 series | The command has been accepted, but the requested action is on hold, pending receipt of further information. |
| 331 | User name okay, need password. |
| 332 | Need account for login. |
| 350 | Requested file action pending further information |
| 400 series | The command was not accepted and the requested action did not take place, but the error condition is temporary and the action may be requested again. |
| 421 | Service not available, closing control connection. This may be a reply to any command if the service knows it must shut down. |
| 425 | Can't open data connection. |
| 426 | Connection closed; transfer aborted. |
| 430 | Invalid username or password |
| 434 | Requested host unavailable. |
| 450 | Requested file action not taken. |
| 451 | Requested action aborted. Local error in processing. |
| 452 | Requested action not taken. Insufficient storage space in system. File unavailable (e.g., file busy). |
| 500 series | Syntax error, command unrecognized and the requested action did not take place. This may include errors such as command line too long. |
| 501 | Syntax error in parameters or arguments. |
| 502 | Command not implemented. |
| 503 | Bad sequence of commands. |
| 504 | Command not implemented for that parameter. |
| 530 | Not logged in. |
| 532 | Need account for storing files. |
| 534 | Could Not Connect to Server - Policy Requires SSL |
| 550 | Requested action not taken. File unavailable (e.g., file not found, no access). |
| 551 | Requested action aborted. Page type unknown. |
| 552 | Requested file action aborted. Exceeded storage allocation (for current directory or dataset). |
| 553 | Requested action not taken. File name not allowed. |
| 600 series | Replies regarding confidentiality and integrity |
| 631 | Integrity protected reply. |
| 632 | Confidentiality and integrity protected reply. |
| 633 | Confidentiality protected reply. |