mailto(admin@db.debian.org) manpage(ud-mailgate)(1)(28 Sep 1999)(userdir-ldap)() manpagename(ud-mailgate)(PGP mail gateway to the LDAP directory) manpagesynopsis() ud-mailgate function manpagedescription() ud-mailgate implements a PGP secured mail gateway to an LDAP directory that allows users to safely and conviently effect changes to their entries. It makes use of PGP signed input messages to positivly identify the user and to confirm the validity of the request. Furthermore it implements a replay cache that prevents the gateway from accepting the same message more than once. There are three functions logically split into 3 sperate email addresses that are implemented by the gateway: bf(ping), bf(new password) and bf(changes). The function to act on is the first argument to the program. ud-mailgate was designed to take its message on stdin from a mailsystem like Exim, with full message headers intact. It transparently decodes PGP/MIME and PGP clearsigned messages and passes them through GnuPG for verification. Support for PGP2.x users is maintained by passing options to GunPG that generate encrypted messages they are able to decode, however this option is only enabled for PGP2.x keys, OpenPGP keys use the new packet formats. Error handling is currently done by generating a bounce message and passing descriptive error text to the mailer. For mailers like Exim this generates a very hard to read message, but it does have the relevent information embedded in it. manpagesection(PING) The ping command simply returns the users public record. It is usefull for testing the gateway and for the requester to get a basic dump of their record. In future this address might 'freshen' the record to indicate the user is alive. Any PGP signed message will produce a reply. manpagesection(NEW PASSWORD) If a user looses their password they can request that a new one be generated for them. This is done by sending the phrase "Please change my Debian password" to chpasswd@db.debian.org. The phrase is required to prevent the daemon from triggering on arbitary signed email. The best way to invoke this feature is with verb(echo "Please change my Debian password" | gpg --clearsign | mail chpasswd@db.debian.org) After validating the request the daemon will generate a new random password, set it in the directory and respond with an ecrpyted message containing the new password. The password can be changed using one of the other interface methods. manpagesection(CHANGES) An address is provided for making almost arbitary changes to the contents of the record. The daemon parse its input line by line and acts on each line in a command oriented manner. Anything, except for passwords, can be changed using this mechanism. Note however that because this is a mail gateway it does stringent checking on its input. The other tools allow fields to be set to virtually anything, the gateway requires specific field formats to be met. startdit() dit(Arbitary Change) A line of the form bf('field: value') will change the contents of the field to value. Some simple checks are performed on value to make sure that it is not sent to nonsense. The values that can be changed are: c, l, facsimiletelephonenumber, telephonenumber, postaladdress, postalcode, loginshell, emailforward, ircnick, onvacation, and labledurl. See ud-info(1) for information on the meanings of each field type. dit(Latitude/Longitude Change) The daemon has a special parser to help changing latitude and longitude values. It accepts several common formats for position information and converts them to one of the standard forms. The permitted types are verb(D = Degrees, M = Minutes, S = Seconds, x = n,s,e,w +-DDD.DDDDD, +- DDDMM.MMMM, +-DDDMMSS.SSSS [standard forms] DDxMM.MMMM, DD:MM.MMMM x, DD:MM:SS.SSS X) and the request format is bf('Lat: xxx Long: xxx') where xxx is one of the permitted types. The resulting response will include how the input was parsed and the value in decimal degrees. dit(SSH RSA Authentication key load) Part of the replicated dataset is a virtual .ssh/authorized_keys file for each user. The change address is the simplest way to set the RSA key(s) you intend to use. Simply place a key on a line by itself, the full SSH key format specification is supported, see sshd(8). Probably the most common way to use this function will be verb(cat .ssh/identity.pub | gpg --clearsign | mail change@db.debian.org) which will set the authentication key to the identity you are using. Multiple keys per user are supported, but they must all be sent at once. dit(DNS Zone Entry) The only way to get a debian.net address is to use this mail gateway. It will verify the request and prevent name collisions automatically. Requests can take two forms: bf('foo in a 1.2.3.4') or bf('foo in cname foo.bar.') The precise form is critical and must not be deviated from. Like the SSH function above, multiple hosts are supported, but they must all be sent at once. The debian.net zone is only reloaded once per day at midnight -0700. dit(Show Function) If the single word bf('show') appears on a line then a PGP encrypted version of the entire record will be attached to the result email. dit(Erasing an entry) The command bf('del foo') can be used to erase any of the entries settable by the user. The erasable attributes are: c, l, facsimiletelephonenumber, telephonenumber, postaladdress, postalcode, emailforward, ircnick, onvacation, labeledurl, latitude, longitude, and sshrsaauthkey. enddit() After processing the requests the daemon will generate a report which contains each input command and the action taken. If there are any parsing errors processing stops immediately, but valid changes up to that point are processed. manpagesection(NOTES) In this document PGP refers to any message or key that GnuPG is able to generate or parse, specificaly it includes both PGP2.x and OpenPGP (aka GnuPG) keys. Due to the replay cache the clock on the computer that generates the signatures has to be accurate to at least one day. If it is off by several months or more then the deamon will outright reject all messages. Examples are given using GnuPG, but PGP 2.x can also be used. The correct options to generate a clear signed ascii armored message in 'filter' mode are bf(pgp -fast) which does the same as bf(gpg --clearsign) Debian.org machines rely on secured replication to transfer login data out of the database. Replication is performed at 15 min intervals so it can take a short while before any changes made take effect. manpagefiles() itemize( it() /etc/userdir-ldap/userdir-ldap.conf Configuration variables to select what server and what base DN to use. ) manpageauthor() userdir-ldap was written by Jason Gunthorpe .