Commit Graph

225 Commits

Author SHA1 Message Date
38c333045b
roles/common: bring Ubuntu firewall changes to Debian 11
Note that there is currently an issue loading the spamhaus rules on
Debian 11 when using ipsets with firewalld and the nftables backend.
The bug is apparently caused by overlapping CIDR segments, and the
solution appears to be that we need to manually aggregate them with
a tool like aggregate6 (Python).

See: https://bugzilla.redhat.com/show_bug.cgi?id=1836571
See: https://wiki.fysik.dtu.dk/it/Linux_firewall_configuration#using-ipsets-in-firewalld-on-rhel-centos-8
See: https://github.com/job/aggregate6
2021-07-24 23:09:33 +03:00
d4ede33099
roles/common: Don't configure apt sources on ARM
I was using this on Ubuntu, but might as well bring it here too so
that I can run Debian on Scaleway's ARM instances, for example.
2021-07-24 22:32:20 +03:00
0bad75788d
roles/common: Add encryption settings to Debian 11 sshd_config
Mostly based on the ssh-audit policy for OpenSSH 8.4, but with any
algorithms using less than 256 bits removed. NSA's Suite B removed
these long ago, and the new CNSA suite only uses 256 and up.

See: https://github.com/jtesta/ssh-audit/blob/master/src/ssh_audit/policy.py
See: https://en.wikipedia.org/wiki/Commercial_National_Security_Algorithm_Suite
2021-07-24 22:28:59 +03:00
892033b880
roles/common: port common settings to Debian 11 sshd_config
Still need to add the encryption settings.
2021-07-22 14:16:20 +03:00
7c6ab2a652 roles/common: Add sshd_config from Debian 11 RC2 2021-07-22 14:15:00 +03:00
1c95c1faa8
roles/common: Update KexAlgorithms in Ubuntu 20.04 sshd_config
Recommended by ssh-audit. Note that curve25519-sha256 is the new name
for the previously private implementation in libssh.
2021-07-22 12:57:31 +03:00
9ea14de6f5
roles/common: Remove Encrypt-and-MAC modes from Ubuntu 20.04 sshd_config
Recommended by ssh-audit, but also generally the concensus for a few
years that Encrypt-and-MAC is hard to get right. OpenSSH has several
Encrypt-then-MAC schemes available so we can use those.

See: https://www.daemonology.net/blog/2009-06-24-encrypt-then-mac.html
2021-07-22 12:48:12 +03:00
9b7a31ebf9
roles/common: Remove 00-persistent-journal.conf
This was to enable the persistent systemd journal, but it is no lo-
nger needed as of Ubuntu 18.04 and Debian 11. I had removed the ta-
asks long ago, but forgot to remove this file.
2021-07-21 10:02:33 +03:00
d7c34a30a3
roles/common: Add Spamhaus DROP lists to firewalld ipsets
This configures the recommended DROP, EDROP, and DROPv6 lists from
Spamhaus as ipsets in firewalld. First we copy an empty placeholder
ipset to seed firewalld, then we use a shell script to download the
real lists and activate them. The same shell script is run daily as
a service (update-spamhaus-lists.service) by a systemd timer.

I am strictly avoiding any direct ipset commands here because I want
to make sure that this works on older hosts where ipsets is used as
well as newer hosts that have moved to nftables such as Ubuntu 20.04.
So far I have tested this on Ubuntu 16.04, 18.04, and 20.04, but ev-
entually I need to abstract the tasks and run them on CentOS 7+ as
well.

See: https://www.spamhaus.org/drop/
2021-07-21 09:34:51 +03:00
531ff99af0
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

  $ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
    confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
    -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
    -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2021-07-04 11:15:32 +03:00
31a3f5832a
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

  $ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
    confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
    -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
    -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2021-05-20 10:20:47 +03:00
4150dac57b
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

  $ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
    confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
    -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
    -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2021-04-13 12:11:11 +03:00
58bc9d191f
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

  $ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
    confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
    -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
    -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2021-03-24 10:02:43 +02:00
63a836e2a7
roles/common: Update Tarsnap GPG key
Apparently this changed since I last ran the tarsnap task.
2021-02-13 12:57:17 +02:00
cd4411260c
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

  $ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
    confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
    -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
    -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2021-02-07 15:56:33 +02:00
e1b412bfff
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

  $ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
    confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
    -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
    -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
  $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2020-12-23 09:01:08 +02:00
4edf92fe0d
roles/common: Allow adding extra SSH users 2020-12-08 23:15:51 +02:00
dd2f65947d
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

    $ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
      confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
      -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
      -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

    $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
    $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2020-11-06 15:44:57 +02:00
f4b104953c
roles/common: Use correct Ansible version comparison
The major version is "16", not "16.04".
2020-07-27 14:23:58 +03:00
72b8b193b5
Remove support for Debian 9 and Ubuntu 16.04 2020-07-14 09:45:33 +03:00
539f081d4d
roles/common: Remove storage-specific tweaks
We don't have any "storage" group. This was ported from somewhere
else and I didn't notice that code.
2020-07-14 09:10:07 +03:00
5282154d7d
roles/common: Disable Canonical spam in MOTD 2020-06-25 21:12:00 +03:00
99b55403d3
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

$ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
  confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
  -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
  -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

    $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
    $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2020-06-21 16:31:09 +03:00
40ac858d60 roles/common: Ignore errors removing snaps
If the snap binary doesn't even exist then it means we've probably
already run this playbook and removed all installed snaps as well.
2020-06-08 12:15:29 +03:00
ba3004ef2b roles/common: Don't run rc.local task on Ubuntu 20.04
We haven't actually used rc.local since Ubuntu 16.04. Now anything
that we need to run at boot we can do with systemd anyways.
2020-06-08 12:15:29 +03:00
ef6ce2335e roles/common: Remove systemd-journald drop-in
Older Ubuntus originally didn't use a persistent journal, which was
somewhat of a surprise when looking at logs after a few months. Now
this does not seem to be an issue since Ubuntu 18.04. As for CentOS
I do not use that distro here so I don't need to care.
2020-06-08 12:15:29 +03:00
6fcb1290fe roles/common: Port sshd_config changes from Debian 10 to Ubuntu 20.04
By now the recommendations we were using as guidance are five years
old. The ciphers have not changed much since then.
2020-06-08 12:15:29 +03:00
5a58d93dfe roles/common: Import sshd_config for Ubuntu 20.04 2020-06-08 12:15:29 +03:00
870bdbfcc3 roles/common: Harden fail2ban service on Ubuntu 20.04 2020-06-08 12:15:29 +03:00
96f62a17d1 roles/common: Use nftables backend in firewalld on Ubuntu 20.04
The nftables backend should be more performant and flexible. I had
been planning to use it on Ubuntu 18.04 and Debian 10 as well, but
there were issues with the specific versions used in those distros.

See: https://firewalld.org/2018/07/nftables-backend
2020-06-08 12:15:29 +03:00
29bbc14068 roles/common: Remove ufw from Ubuntu systems
We never used this simple firewall utility and in at least one case
a user on the server tried to use it and messed up the rules I had
set via firewalld.
2020-06-08 12:15:29 +03:00
7288a85e72 roles/common: Remove snaps on Ubuntu 20.04
The list of pre-installed snaps and system packages is different on
Ubuntu 20.04 than it was in previous LTS releases.

See: https://www.kevin-custer.com/blog/disabling-snaps-in-ubuntu-20-04/
2020-06-08 12:15:29 +03:00
5242493b53
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

$ curl -G https://api.abuseipdb.com/api/v2/blacklist -d \
  confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" \
  -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' \
  -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

    $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
    $ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2020-06-03 10:10:49 +03:00
ed2e0efd9c
roles/common: Actually remove annoying Ubuntu motd spam 2020-04-24 22:37:50 +03:00
03254d6aae
roles/common: Use normal tarsnap GPG packaging key 2020-03-16 18:03:53 +02:00
2dc195b33c
Use version() instad of version_compare()
This changed in Ansible 2.5 apparently.

See: https://docs.ansible.com/ansible/latest/user_guide/playbooks_tests.html
2020-03-09 15:20:51 +02:00
d78015c92c
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

$ curl -G https://api.abuseipdb.com/api/v2/blacklist -d confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy:

$ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv4.xml
$ tidy -xml -utf8 -m -iq -w 0 roles/common/files/abusers-ipv6.xml
2019-12-23 11:39:35 +02:00
e4c3376383
roles/common: Fix logic in enabling individual calls in firewalld 2019-12-10 13:45:00 +02:00
e1c7bbe096
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

$ curl -G https://api.abuseipdb.com/api/v2/blacklist -d confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy.
2019-11-13 11:35:14 +02:00
8edc68ca3c
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

$ curl -G https://api.abuseipdb.com/api/v2/blacklist -d confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" -H "Accept: text/plain" | sort | sed -e '/:/w /tmp/ipv6.txt' -e '/:/d' > /tmp/ipv4.txt

I manually add the XML formatting to each file and run them through
tidy.
2019-11-04 10:12:17 +02:00
2631f76c6d
roles/common: Use iptables backend for firewalld on Debian
For some reason the nftables set support in firewalld doesn't seem
to be working. I see that sets (aka ipsets in nftables lingo) are
created, but they are empty. For now I will just leave these tasks
as they are to revert the behavior on current hosts (should do no
change on new installed, as the regexp won't match).
2019-10-26 19:34:25 +02:00
919fbbbcd9
roles/common: Make sure fail2ban is started 2019-10-26 17:14:28 +02:00
9f27cda97b
roles/common: Update list of abusive IP addresses
This comes from the AbuseIPDB with a confidence level of 95%. I use
the following command to download and sort the IPs:

$ curl -G https://api.abuseipdb.com/api/v2/blacklist -d confidenceMinimum=95 -H "Key: $ABUSEIPDB_API_KEY" -H "Accept: text/plain" | sort > /tmp/ips.txt

I manually remove the IPv6 addresses and save them to a different
filr, then I add the XML formatting to files and run them through
tidy.
2019-10-26 17:09:18 +02:00
d8d8a01a5f
roles/common: Remove SSH rate limiting from firewalld
Rather than a simple rate limit, I'm now using fail2ban to ban IPs
that actually fail to login.
2019-10-26 16:41:42 +02:00
4710ee6f07
roles/common: Bump version checks to Ubuntu 16.04 2019-10-26 16:40:14 +02:00
9db104efa6
roles/common: Bump version checks to Debian 9 2019-10-26 16:37:27 +02:00
0605f70f2e
roles/common: Add support for fail2ban
This is active banning of IPs that are brute forcing login attempts
to SSH, versus the passive banning of 10,000 abusive IPs from the
abuseipdb.com blacklist. For now I am banning IPs that fail to log
in successfully more than twelve times in a one-hour period, but
these settings might change, and I can override them at the group
and host level if needed.

Currently this works for CentOS 7, Ubuntu 16.04, and Ubuntu 18.04,
with minor differences in the systemd configuration due to older
versions on some distributions.

You can see the status of the jail like this:

    # fail2ban-client status sshd
    Status for the jail: sshd
    |- Filter
    |  |- Currently failed: 0
    |  |- Total failed:     0
    |  `- Journal matches:  _SYSTEMD_UNIT=sshd.service + _COMM=sshd
    `- Actions
       |- Currently banned: 1
       |- Total banned:     1
       `- Banned IP list:   106.13.112.20

You can unban IPs like this:

    # fail2ban-client set sshd unbanip 106.13.112.20
2019-10-26 16:36:07 +02:00
f3614d4ad4
roles/common: Remove buster-backports
I was using it to get iptables 1.8.3 to work around an issue with
firewalld, but I've solved that another way.
2019-10-18 22:56:52 +03:00
25e0fd3557
roles/common: Use individual calls with firewalld
Seems to work around an issue when firewalld is using the nftables
backend with iptables 1.8.2 on Debian 10. Alternatively I could go
back to using the iptables backend... hmm.

See: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=914694
2019-10-18 22:49:29 +03:00
cac38af09b
roles/common: Use nftables firewalld backend on Debian 10
nftables is the iptables replacement. There is support for nftables
in firewalld since v0.6.0.

See: https://firewalld.org/2018/07/nftables-backend
2019-10-18 19:02:17 +03:00