eVote Adds Elections to Mailing Lists
eVote's e-mail list interface provides three levels of participation:
Voter: users can vote and change their votes; they also have the same power to query the data, as does the administrator of the poll and the list's owner.
User/administrator: any user can initiate a poll. Under ordinary circumstances, only the user who starts a poll can close or drop it from the data.
List owner: some commands are password-protected. These provide overriding powers so the owner can close/drop any poll, change the voting privileges or move a participant's ballot to a new e-mail address. The list's owner also retains the same responsibilities and powers as owners of lists without eVote.
The overall architecture of the e-mail facility is shown in Figure 1. eVote is five programs that work together: eVote_Clerk, the Clerk; eVote_insert, the e-mail list user interface; eVote_mail, the mail administrator's utility interface; eVote_petition, the interface for signers of petitions; and eVote, the command center for controlling the Clerk.
eVote_Clerk runs continuously in the computer's background, establishing new polls, dropping old items, accepting, tallying, storing and reporting votes and statistics. eVote_Clerk has no direct user interface. It is started, controlled and stopped by the eVote executable.
The eVote_insert executable is the e-mail interface that coordinates with Mailman, the popular open-source e-mail list server. Mailman provides the discussion medium; eVote provides the voting facility. This cooperation is configured in the alias file of the mail transfer agent (MTA). Exception: if the MTA is Exim and the listserver is Mailman, Exim's configuration file handles lists and the cooperation with eVote.
eVote_mail allows the site administrator to synchronize the Clerk's list of subscribers to Mailman's list. The site administrator can use this program to block voting from a specific address or to drop an address from all lists. Similarly, this program can delete stale messages that have been awaiting confirmation.
Two facilities are present in eVote's e-mail interface: polling in e-mail lists and petition support. The petition facility allows anyone to participate, while the e-mail list facility allows only addresses on the e-mail list to participate. Petitions are administered collaboratively by members of a petition list, which is any list whose name starts with the word petition, say, petitiona, petitionb and so on. Polls initiated in petition lists have the option of being open to nonmembers.
The eVote executable is the command center for eVote and can be called with various arguments. Depending on the argument, eVote will start, stop or check the Clerk, check and synchronize data, or flush or restart the log.
Mailman can be invoked by any MTA such as sendmail, Exim or Postfix. Normally, mail directed to the e-mail list address is piped to Mailman's wrapper program to control permissions on the process and to limit the programs executed through the pipe. The wrapper then calls Mailman's post script to broadcast the mail to the list's addresses.
The alias entry for the regular Mailman list called sample might look like:
sample: "|/home/mailman/bin/wrapper post sample" sample-admin: "|/home/mailman/bin/wrapper mailowner sample" sample-request: "|/home/mailman/bin/wrapper mailcmd sample" sample-owner: sample-admin
The mailcmd program needs a few new lines of code to tell it to send e-mail notification to eVote whenever someone successfully subscribes or unsubscribes from the list.
Mail to be broadcast to list members is piped to Mailman's post program by the sample: alias.
eVoting is turned on by inserting eVote_insert in the pipe:
sample: "|/home/mailman/bin/wrapper eVote_insert post sample"
Wrapper's C source code gets a few modifications so it will allow eVote_insert to be run. Now eVote gets a first look at all the mail coming into the list's broadcasting address. If the first word in the incoming message is eVote, eVote_insert intercepts the message for vote processing. Otherwise, it sends the message on to post (Figure 3).
Petition lists are set up exactly as other eVote lists. As previously mentioned, eVote recognizes them as special because their names start with “petition”. These are intended to be used for collaborating on the administration of a petition. Members of a petition list can discuss and poll themselves, and they also have the power to set up a petition for the whole world to sign. These petitions can include any of eVote's vote types, and they always invite a comment from the signers.
The petition facility has an additional alias for receiving signatures:
eVote: "|/home/mailman/mail/wrapper eVote_petition"
The one eVote_petition alias processes signatures for all petition lists at the facility.
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