CS161 Programming Assignment 5: IMAP Server (part 1)
Due date: Friday, December 2nd, 10 PM.
2) CS161 Environment Setup
Add this line to your shell startup scripts:
Your fifth programming task is to implement
an IMAP server in C++ using NMSTL. As you know by now,
IMAP is described in RFC 3501. Your server
will be due in two pieces. The first part will consist of implementing
all commands that are available in the "Not Authenticated" state:
AUTHENTICATE, CAPABILITY, LOGIN,
LOGOUT, NOOP, and STARTTLS, plus two extra
useful commands: LIST and SEARCH.
As usual, you will implement your server with an event-based
architecture to support large numbers of concurrent connections.
Again, you may use external processes to avoid blocking in your main
loop, but you should avoid starting a process for each connection.
4) Assignment Specification
- You are implementing six IMAP commands. However, you should
structure your code to support adding new commands rapidly (in part
- Your AUTHENTICATE and STARTTLS commands will be
barebones. You will reply BAD or NO as appropriate, because you will
not support SSL or any extra authentication mechanisms.
- LOGIN should support authentication based on the
contents of a file in the current directory, login.txt. You
should describe and implement a mechanism that avoids storing
passwords as cleartext in this file.
- Your SEARCH command need not handle the optional charset. You do
not need to handle any search keys that require you to parse email
headers or dates (BCC, BEFORE, CC, FROM, etc). Other keys, such as
those that handle flags, should be handled. You should also handle
- Listen on a specific port with command line switch -p
port, so that you can start your servers on department machines
without root privileges.
- You program should support a way to add a user to
login.txt rather than start up as a server. ./imapd jj
hippo Should modify login.txt to allow jj to login with
- You should describe, in a README, your program as it exists,
how commands are added, and how you intend to implement
mailboxes (and folders) in the second phase. Describe your
intended file usage, as well as your program structure to avoid
blocking, and mailbox corruption from simultaneous clients.
You should be able to use your IMAP client from previous labs to
test your server. Testing with other clients (pine, mozilla,
fetchmail, etc) may also be useful.
Remember to read RFC
2683 which contains advice for IMAP developers (clients and
6) Support Code To help you get started we're giving you
access to two fingerd implementations. You may take code and
ideas from these servers. They are in
/course/cs161/asgn/imapd/fingerd. If you had troule with
the fingerd, this should help you get started. We recommend
taking a little time and becoming familar with both, then taking
the best of both worlds.
7) Submitting your code To submit your code, run the following
script inside the top level directory of your work:
Please contact the TAs if you have problems submitting. For your own
sanity, don't leave your submission until the minute before the
8) Grading scheme
Your code will be graded on the following factors (and their
|Documentation and design (login.txt, part 2, etc):
|Functionality (non-blocking, error reporting, etc):
|Robustness (malicious input, many connections, etc):