FeministWiki:Technical documentation

Revision as of 15:51, 23 September 2018 by SocJusWiz (talk | contribs) (→‎Certs)

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 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 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

The following entries are used 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
TXT @ google-site-verification=<key> Google Site Verification

And the following SRV records for XMPP:

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

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 command while TCP port 80 is free (e.g. stop Apache first):

letsencrypt certonly --authenticator standalone -d "$(tr '\n' ',' < /root/etc/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 doesn't work well on a "dumb" terminal such as an Emacs shell buffer. Make sure to 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.

SMTP

Host: smtp.feministwiki.org
Software: Postfix

FeministMail uses the Postfix SMTP server, using SASL authentication through Dovecot and LDAP-based virtual mail boxes under /home/vmail.

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.