Network Program Implementation

Due: 4:00pm, Thursday, December 12, 2024

Network Program Implementation – File Server

In this assignment you will develop a file server application The server will be a concurrent, connection-oriented multi-client file server. The concurrent server can be implemented utilizing either processes or threads. The client application will be similar to the sftp program and implement a subset of the sftp commands.

Server Specifications

• The name of the compiled program must be fileserver.

• The input to the program must be in the form of command line arguments as follows:

  • -p <string> (required) port
  • -d <string> (required) directory to serve files from

• The server must ensure that files are only served and created from within the given directory and its subdirectories. It is a security risk if a client can obtain files from arbitrary ancestor directories. If a client requests such a file, this must be indicated to the client somehow.

• The server must be able to gracefully shutdown. If the server receives a CTRL-c to kill it, the server should send a message to all clients indicating it will be shutting down in x seconds, then wait x seconds and gracefully close. This should be done by using a signal handler for the SIGINT signal.

Client Specifications

• The name of the compiled program must be fileclient.

• The input to the program must be in the form of command line arguments as follows:

  • -h <string> (required) host
  • -p <string> (required) port

• The client must be a read-eval-print loop (REPL) application, that is, is a simple interactive application that takes single user inputs, executes them, and returns the result to the user. These are the commands that the client must implement:

  • exit – quit the application.

  • cd [path] – Change remote directory to path. If path is not specified, then change directory to the one the session started in.

  • get [-R] remote-path [local-path] – Retrieve the remote-path and store it on the local machine. If the local path name is not specified, it is given the same name it has on the remote machine.

    If the -R flag is specified then directories will be copied recursively.

  • help – Display help text.

  • lcd [path] – Change local directory to path. If path is not specified, then change directory to the local user’s home directory.

  • lls [path] – Display local directory listing of either path or current directory if path is not specified.

  • lmkdir path – Create local directory specified by path.

  • lpwd – Print local working directory.

  • ls [path]Display a remote directory listing of either path or the current directory ifpath` is not specified.

  • mkdir path – Create remote directory specified by path.

  • put [-R] local-path [remote-path] – Upload local-path and store it on the remote machine. If the remote path name is not specified, it is given the same name it has on the local machine.

    If the -R flag is specified then directories will be copied recursively.

  • pwd - Display remote working directory.

Makefile Specifications

• The makefile should build both the fileclient and fileserver applications.

• Add a rule called clean to remove any temporary files and the webserver executable.

Readme File Specifications

Each team will create a readme file for their application. The readme file will include the following sections, at a minimum:

• ID block

• How to build and run the client and server

• File/folder manifest identifying the purpose of each file/folder included in the project

• Responsibility list – a list with and item for each team member and the aspects of the project to which they contributed

• Protocol – the specific details of your developed protocol, including the wire protocol (that is, how the data is serialized to be sent or received over the socket)

• Assumptions – clearly list and describe any assumptions made about running the application or how the application works

• Discussion on your development process, including any decisions and/or major problems you encountered and your solution for each

• Status – current status of the applications in terms of specifications, and any known issues with the applications

Files to Submit

To submit your assignment, create a zip file of a DIRECTORY named final-project containing the required files. Then submit that file to the appropriate folder on D2L.

The submission must include:

• All source files

• Makefile or equivalent script to compile all source files, if necessary

• Readme file