1 #use wml::db.d.o title="LDAP Gateway"
7 The LDAP directory has a PGP secured mail gateway that
8 allows users to safely and conveniently effect changes to their entries. It
9 makes use of PGP signed input messages to positively identify the user and
10 to confirm the validity of the request. Furthermore it implements a replay
11 cache that prevents the gateway from accepting the same message more than
15 There are three functions logically split into 3 separate email addresses
16 that are implemented by the gateway: <b>ping</b>, <b>new password</b> and
17 <b>changes</b>. The function to act on is the first argument to the program.
20 Error handling is currently done by generating a bounce message and passing
21 descriptive error text to the mailer. This can generate a somewhat hard to
22 read error message, but it does have all the relevant information.
25 The ping command simply returns the users public record. It is useful for
26 testing the gateway and for the requester to get a basic dump of their
27 record. In future this address might 'freshen' the record to indicate the
28 user is alive. Any PGP signed message will produce a reply.
31 If a user loses their password they can request that a new one be generated
32 for them. This is done by sending the phrase "Please change my Debian
33 password" to chpasswd@db.debian.org. The phrase is required to prevent the
34 daemon from triggering on arbitrary signed email. The best way to invoke this
36 <pre>echo "Please change my Debian password" | gpg --clearsign | mail chpasswd@db.debian.org</pre>
37 After validating the request the daemon will generate a new random password,
38 set it in the directory and respond with an encrypted message containing the
39 new password. The password can be changed using one of the other interface
43 An address (changes@db.debian.org) is provided for making almost arbitrary
44 changes to the contents of the record. The daemon parses its input line by
45 line and acts on each line in a command oriented manner. Anything, except for
46 passwords, can be changed using this mechanism. Note however that because
47 this is a mail gateway it does stringent checking on its input. The other
48 tools allow fields to be set to virtually anything, the gateway requires
49 specific field formats to be met.
52 <li>A line of the form <tt>'field: value'</tt> will change the contents of
53 the field to value. Some simple checks are performed on value to make sure
54 that it is not set to nonsense. You can't set an empty string as
55 value, use <tt>del</tt> instead (see below). The values that can
57 <b>c</b>, <b>l</b>, <b>facsimileTelephoneNumber</b>, <b>telephoneNumber</b>,
58 <b>postalAddress</b>, <b>postalCode</b>,
59 <b>loginShell</b>, <b>emailForward</b>,
60 <b>jabberJID</b>, <b>ircNick</b>, <b>icqUin</b>,
63 <b>birthDate</b> (YYYYMMDD),
64 <b>mailDisableMessage</b>,
65 <b>mailGreylisting</b> (TRUE|FALSE),
66 <b>mailCallout</b> (TRUE|FALSE),
67 <b>mailContentInspectionAction</b> (markup|blackhole|reject)
68 <b>mailDefaultOptions</b> (TRUE|FALSE),
72 <li>A line of the form <tt>'del field'</tt> will completly remove all
73 occurrences of a field. Useful e.g. to unset your vacation status.
74 The fields that can be deleted are:
75 <b>c</b>, <b>l</b>, <b>facsimileTelephoneNumber</b>, <b>telephoneNumber</b>,
76 <b>postalAddress</b>, <b>postalCode</b>, <b>emailForward</b>,
77 <b>onVacation</b>, <b>labeledURI</b>, <b>latitude</b>, <b>longitude</b>, <b>dnsZoneEntry</b>,
78 <b>ircNick</b>, <b>jabberJID</b>, <b>icquin</b>,
80 <b>mailGreylisting</b>,
84 <b>mailDisableMessage</b>,
86 <b>mailContentInspectionAction</b>,
87 <b>mailDefaultOptions</b>,
90 <b>jpegPhoto</b>, <b>VoIP</b>
92 <li>The daemon has a special parser to help changing latitude and longitude
93 values. It accepts several common formats for position information and
94 converts them to one of the standard forms. The permitted types are
95 <pre>D = Degrees, M = Minutes, S = Seconds, x = n,s,e,w
96 +-DDD.DDDDD, +- DDDMM.MMMM, +-DDDMMSS.SSSS [standard forms]
97 DDxMM.MMMM, DD:MM.MMMM x, DD:MM:SS.SSS X)</pre>
98 and the request format is <tt>'Lat: xxx Long: xxx'</tt> where <tt>xxx</tt>
99 is one of the permitted types. The resulting response will include how the
100 input was parsed and the value in decimal degrees.
103 Part of the replicated dataset is a virtual .ssh/authorized_keys file for
104 each user. The change address is the simplest way to set the RSA key(s) you
105 intend to use. Simply place a key on a line by itself, the full SSH key
106 format specification is supported, see sshd(8). Probably the most common way
107 to use this function will be
108 <pre>cat .ssh/id_rsa.pub | gpg --clearsign | mail changes@db.debian.org</pre>
109 which will set the authentication key to the identity you are using.
111 Multiple keys per user are supported, but they must all be sent at once.
112 To retrieve the existing SSH keys in order to merge existing keys
113 with new ones, use the 'show' command documented below.
115 Keys can be exported to a subset of machines by prepending
116 <b>allowed_hosts=$fqdn,$fqdn2</b> to the specific key. The allowed machines
117 must only be separated by a comma.
121 # cat .ssh/debian-machines.pub
122 allowed_hosts=ravel.debian.org,gluck.debian.org ssh-rsa AAAAB3Nz..mOX/JQ== user@machine
123 ssh-rsa AAAAB3Nz..uD0khQ== user@machine
126 <li>RBL, RHSBL, and whitelists can only be updated via the mail gateway. Like
127 DNS and ssh keys, any list specified must be specified in its enterity. The format is:
128 <b>listtype</b> <b>dns.domain.of.rbl/IP to whitelist</b> where listtype is one of mailRBL,
129 mailRHSBL, and mailWhitelist
131 <li>The only way to get a dnsZoneEntry record for a debian.net address is to
132 use the mail gateway. It will verify the request and prevent name collisions
133 automatically. Requests can take several forms:
135 <dt><tt>foo in a 192.0.2.123</tt></dt>
136 <dd>to create an A record for <tt>foo.debian.net</tt></dd>
138 <dt><tt>foo in aaaa 2001:DB8::12:34</tt></dt>
139 <dd>to create an AAAA record for <tt>foo.debian.net</tt></dd>
141 <dt><tt>foo in cname example.org.</tt></dt>
142 <dd>to create a CNAME record for <tt>foo.debian.net</tt></dd>
144 <dt><tt>'foo in txt plain text here'</tt></dt>
145 <dd>to create a TXT record for <tt>foo.debian.net</tt></dd>
147 <dt><tt>foo in mx 10 example.org.</tt></dt>
148 <dd>to create an MX record for <tt>foo.debian.net</tt></dd>
151 Please note the trailing dot for the CNAME and MX records.
152 Note that you cannot combine CNAME with any other record types.
153 The precise form is critical and must not be deviated from.
154 Like the SSH function above, multiple hosts are supported, but they must all
155 be sent at once. The debian.net zone is reloaded hourly.
157 <li>If the single word <b>show</b> appears on a line then a PGP encrypted version
158 of the entire record will be attached to the resulting email. For example:
159 <pre>echo show | gpg --clearsign | mail changes@db.debian.org</pre>
163 After processing the requests the daemon will generate a report which contains
164 each input command and the action taken. If there are any parsing errors
165 processing stops immediately, but valid changes up to that point are
170 In this document PGP refers to any message or key that GnuPG is
171 able to generate or parse, specifically it includes both PGP2.x and OpenPGP
174 Due to the replay cache the clock on the computer that generates the
175 signatures has to be accurate to at least one day. If it is off by several
176 months or more then the daemon will outright reject all messages.
178 Examples are given using GnuPG, but PGP 2.x can also be used. The correct
179 options to generate a clear signed ascii armored message in 'filter' mode
180 are <tt>pgp -fast</tt> which does the same as <tt>gpg --clearsign</tt>
182 Debian.org machines rely on secured replication to transfer login data out
183 of the database. Replication is performed at 15 min intervals so it can take
184 a short while before any changes made take effect.
186 If the mail you're sending to the mail robot is too long for your MUA
187 and gets split, or if you want something that is more robust while copy pasting
188 into a web-mailer, you can try to create a non-clearsigned message and mail
189 that to changes@db.debian.org:
190 <pre>cat .ssh/id_rsa.pub | gpg --armor --sign</pre>