FeministWiki:Technical documentation

    From FeministWiki

    This page documents the FeministWiki's technical infrastructure, the target audience being technicians.

    Hosts

    The following table documents the basic DNS configuration, and can be used as part of the /etc/hosts file on each server to obviate the need for DNS lookups when connecting to one another.

    IP FQDN Host Purpose
    85.214.101.34 feministwiki.org Wiki
    85.214.101.34 www.feministwiki.org www Wiki
    85.214.101.34 ldap.feministwiki.org ldap LDAP
    85.214.101.34 blog.feministwiki.org blog Blogging
    85.214.101.34 chat.feministwiki.org chat Web-client for XMPP
    85.214.101.34 forum.feministwiki.org forum BBS Forum
    85.214.101.34 mail.feministwiki.org mail Web-client for Mail
    85.214.101.34 files.feministwiki.org files File storage
    85.214.101.34 imap.feministwiki.org imap IMAP
    85.214.101.34 pop3.feministwiki.org pop3 POP3
    85.214.101.34 smtp.feministwiki.org smtp SMTP
    85.214.101.34 xmpp.feministwiki.org xmpp XMPP
    85.214.101.34 irc.feministwiki.org irc IRC
    85.214.101.34 social.feministwiki.org social GNU social
    85.214.101.34 add-member.feministwiki.org add-member Add a member

    (As you can see, all services are on the same server for now.)

    Special DNS entries

    For CAA:

    Type Name Flag Tag Value
    CAA @ 0 issue letsencrypt.org
    CAA @ 0 iodef admin@feministwiki.org

    For email:

    Type Host Data Purpose
    MX @ smtp.feministwiki.org Mail server
    TXT @ v=spf1 mx -all SPF
    TXT mail._domainkey v=DKIM1; k=rsa; p=<pubkey> DKIM
    TXT _dmarc v=DMARC1; p=reject; rua=mailto:admin@feministwiki.org DMARC

    For XMPP:

    Type Service Protocol Name Destination Port
    SRV _xmpp-client _tcp @ xmpp.feministwiki.org 5222
    SRV _xmpp-server _tcp @ xmpp.feministwiki.org 5269

    Google Site Verification:

    Type Host Data
    TXT @ google-site-verification=<key>

    SSH access

    FeministWiki hosts have ssh enabled for root access, but password login is disabled. You must own a valid private key to log in.

    Git repo of scripts and configuration

    The following GitHub account hosts repositories with scripts and configuration used by the FeministWiki:

    https://github.com/FeministWiki

    Certs

    The FeministWiki uses LetsEncrypt to acquire digital certificates for encrypted communication.

    To ease use of the letsencrypt command, the file /root/etc/domains contains all the FQDNs used by the FeministWiki, one per line. Given that, the preferred way to populate the /etc/letsencrypt/live/feministwiki.org directory with fresh certs is to run the following commands while TCP port 80 is free (e.g. stop Apache first):

     # Use $() to eliminate the terminating newline, if any.
     domains=$(cat /root/etc/domains)
     
     domains=$(printf '%s' "$domains" | tr '\n' ',')
     
     letsencrypt certonly --authenticator standalone --keep --expand -d "$domains"
    

    Additionally, for programs that require a cert file and its private key in a single combined .pem file, run the following commands to generate such a file:

    cd /etc/letsencrypt/live/feministwiki.org
    cat fullchain.pem privkey.pem > certbundle.pem
    

    The script /root/bin/letsencrypt-refresh does all of the above, so in practice you just need to run the following commands to recreate the cert:

    service apache2 stop  # Assuming Apache is running on the machine
    letsencrypt-refresh
    service apache2 start
    

    The above can be used not only to refresh a cert that's running out, but also to add a new domain to the cert. Just add the domain to /root/etc/domains and run the commands.

    Note that the letsencrypt command may not work well on a "dumb" terminal such as an Emacs shell buffer. If in doubt, run it from within a proper terminal emulator.

    Readability of the key files

    To ensure that processes running under unprivileged users can read key files, ensure that the users they run under are members of the ssl-cert group, which should have read access to the files in /etc/letsencrypt/live/feministwiki.org.

    Services

    This section documents the individual services of the FeministWiki. They should work regardless of what server they're on. I.e. every service could in theory be hosted on its own server.

    LDAP

    Host: ldap.feministwiki.org
    Software: OpenLDAP

    The LDAP service contains the central database of FeministWiki members. The structure looks like this:

    • dc=feministwiki,dc=org
      • ou=members
        • cn=username
          objectClass: inetOrgPerson
          cn: username
          uid: username
          sn: -
          userPassword: {SSHA}saltedhash
          mail: username@feministwiki.org
        • cn=username2
          objectClass: inetOrgPerson
          cn: username2
          uid: username2
          sn: -
          userPassword: {SSHA}saltedhash2
          mail: username2@feministwiki.org
          manager: cn=username,ou=members,dc=feministwiki,dc=org
        • ...
      • ou=groups
        • cn=members
          objectClass: groupOfNames
          cn: members
          member: username
          member: username2
          member: ...

    Notes:

    • The cn (common name) and uid (user ID) fields both contain the username. This is because some software is preconfigured to look at uid, while most look at cn.
    • The sn (surname) field simply contains a minus character as a placeholder, because it's a mandatory field.
    • The manager field is optional and we use it to record the member who added the member in question.

    To make sure passwords are stored with the {SSHA} scheme rather than plain text, the ppolicy "password policy overlay" is used. ZYTRAX has a very nice book about LDAP which documents how to enable this: http://www.zytrax.com/books/ldap/ch6/ppolicy.html

    In short, the steps go as follows (these commands should work verbatim):

    # Add the ppolicy schema
    ldapadd -Y external -H ldapi:/// < /etc/ldap/schema/ppolicy.ldif
    
    # Enable the ppolicy dynamic module
    ldapmodify -Y external -H ldapi:/// <<EOF
    dn: cn=module{0},cn=config
    changetype: modify
    add: olcModuleLoad
    olcModuleLoad: ppolicy
    EOF
    
    # Add the ppolicy overlay with olcPPolicyHashCleartext set to TRUE
    ldapadd -Y external -H ldapi:/// <<EOF
    dn: olcOverlay=ppolicy,olcDatabase={1}mdb,cn=config
    objectClass: olcPPolicyConfig
    olcOverlay: ppolicy
    olcPPolicyHashCleartext: TRUE
    EOF
    

    Wiki

    Host: feministwiki.org, www.feministwiki.org
    Software: MediaWiki

    The wiki uses a MediaWiki installation located at /var/www/wiki/w with the LDAP Authentication plugin for login management and the "Short URL" feature enabled with help of Apache's vhost configuration, which is located at /etc/apache2/sites-available/wiki.conf.

    The wiki uses the SQL database called "feministwiki" and the SQL user of the same name.

    Chat (web interface)

    Host: chat.feministwiki.org
    Software: Converse.js

    The web-interface for the FeministChat uses the full-screen "Impress" variant of the Converse.js XMPP client. The hosted HTML and JS files are located at /var/www/chat, although they load Converse.js as an external script from upstream, which is why the self-hosted HTML and JS are very minimal.

    Forum

    Host: forum.feministwiki.org
    Software: phpBB

    The forum uses a phpBB installation located at /var/www/forum. Most configuration of phpBB, including LDAP authentication, is done through its administration panel. The style used by the forum is essentially Basic Orange, though the logo is changed via an inheriting style called FeministWiki.

    The forum uses the SQL database called "feministforum" and the SQL user of the same name.

    Mail (web interface)

    Host: mail.feministwiki.org
    Software: Roundcube

    The web-interface for the FeministMail uses the Roundcube mail client, installed at /var/www/mail. It uses the standard "larry" style, but with some tweaks to logos and images.

    Files

    Host: files.feministwiki.org
    Software: Nextcloud

    FeministFiles is a Nextcloud installation with some branding, and LDAP authentication, installed at /var/www/files.

    IMAP

    Host: imap.feministwiki.org
    Software: Dovecot

    FeministMail uses the Dovecot IMAP server, configured for LDAP authentication and using virtual mail boxes under /home/vmail.

    POP3

    Host: pop3.feministwiki.org
    Software: Dovecot

    While Dovecot is primarily an IMAP server, it also offers POP3 support, which the FeministWiki installation has enabled.

    SMTP

    Host: smtp.feministwiki.org
    Software: Postfix, OpenDKIM

    FeministMail uses the Postfix SMTP server, using SASL authentication through Dovecot, LDAP-based virtual mail boxes under /home/vmail, and DKIM signing via OpenDKIM. Send a mail to a Gmail account and use the "Show original" feature of Gmail to see if the mail passes SPF, DKIM, and DMARC tests.

    There are also various tools on the web to automatically test the DNS settings for correctness, to check if the domain/IP is on blacklists, etc., which you can find via Google. All in all, FeministMail is probably the most complicated service of the FeministWiki, as far as technical background goes.

    XMPP

    Host: xmpp.feministwiki.org
    Software: ejabberd

    FeministChat uses the ejabberd XMPP server, configured to use LDAP authentication and an LDAP-based shared roster group for all members.

    IRC

    Host: irc.feministwiki.org
    Software: InspIRCd

    FeministIRC uses the InspIRCd IRC server with the ldapauth module for LDAP authentication.

    Add a member

    Host: add-member.feministwiki.org
    Software: custom

    The page to add a new member, hosted at /var/www/add-member, uses a bit of self-written HTML, PHP, and a setuid-root C program to invoke the shell script located at /root/bin/fw-adduser with root privileges.