V8.13.256.2025.10.21

Signed-off-by: Marc S. Weidner <msw@coresecret.dev>
2025-10-21 20:52:39 +01:00
parent 343ae97968
commit 2a866d7520
40 changed files with 200 additions and 116 deletions
--- a/config/hooks/live/0007_update_logrotate.chroot
+++ b/config/hooks/live/0007_update_logrotate.chroot
@@ -20,27 +20,49 @@ rm -f         "/etc/logrotate.conf"
 cat << EOF >| "/etc/logrotate.conf"
 # See "man logrotate" for details. Global options do not affect preceding include directives.

-# rotate log files daily
+# Rotate log files daily
 daily

-# keep 384 daily worth of backlogs
+# Keep 384 daily worth of backlogs.
 rotate 384

-# hard cap: delete rotated logs older than 384 days
+# Hard cap: delete rotated logs older than 384 days.
 maxage 384

-# create new (empty) log files after rotating old ones
+# Do not rotate the log if it is empty (this overrides the ifempty option).
+notifempty
+
+# Create new (empty) log files after rotating old ones.
 create

-# use date as a suffix of the rotated file
+# Use date as a suffix of the rotated file.
 dateext

-# gzip older rotations
+# Use yesterday's instead of today's date to create the dateext extension, so that the rotated log file has a date in its name
+# that is the same as the timestamps within it.
+dateyesterday
+
+# Enable compression
 compress

-# keep the most recent rotation uncompressed for one cycle
+# Use zstd instead of gzip.
+compresscmd /usr/bin/zstd
+
+# File extension for compressed logs.
+compressext .zst
+
+# Set zstd level 3 (default).
+compressoptions -20
+
+# How to decompress for 'logrotate -d' or similar.
+uncompresscmd /usr/bin/unzstd
+
+# Keep the most recent rotation uncompressed for one cycle.
 delaycompress

+# Delete log files using shred -u instead of unlink().
+shred
+
 # packages drop log rotation information into this directory
 include /etc/logrotate.d

--- a/config/hooks/live/9950_fail2ban_hardening.chroot
+++ b/config/hooks/live/9950_fail2ban_hardening.chroot
@@ -24,7 +24,7 @@ sed -i 's/#allowipv6 = auto/allowipv6 = auto/1' /etc/fail2ban/fail2ban.conf
 mv /etc/fail2ban/jail.d/defaults-debian.conf /root/.ciss/dlb/backup/defaults-debian.conf.bak
 chmod 0400 /root/.ciss/dlb/backup/defaults-debian.conf.bak

-cat << 'EOF' >| /etc/fail2ban/jail.d/ciss-default.conf
+cat << EOF >| /etc/fail2ban/jail.d/ciss-default.conf
 # SPDX-Version: 3.0
 # SPDX-CreationInfo: 2025-05-05; WEIDNER, Marc S.; <cendev@coresecret.eu>
 # SPDX-ExternalRef: GIT https://cendev.eu/marc.weidner/CISS.2025.debian.live.builder.git
@@ -37,69 +37,106 @@ cat << 'EOF' >| /etc/fail2ban/jail.d/ciss-default.conf
 # SPDX-Security-Contact: security@coresecret.eu

 [DEFAULT]
-usedns    = yes
-# 127.0.0.1/8  – IPv4 loopback range (local host)
-# ::1/128      – IPv6 loopback
-# fe80::/10    – IPv6 link-local (on-link only; NDP/RA/DAD)
-# fc00::/7     – IPv6 ULA (private LAN addresses)
-# ff00::/8     – IPv6 multicast (not an unicast host)
-# ::/128       – IPv6 unspecified (all zeros; never a real peer)
-ignoreip  = 127.0.0.1/8 ::1/128 fe80::/10 fc00::/7 ff00::/8 ::/128 MUST_BE_SET
-maxretry  = 8
-findtime  = 24h
-bantime   = 24h
+dbpurgeage            = 384d
+#                       127.0.0.1/8 - IPv4 loopback range (local host)
+#                       ::1/128     - IPv6 loopback
+#                       fe80::/10   - IPv6 link-local (on-link only; NDP/RA/DAD)
+#                       ff00::/8    - IPv6 multicast (not an unicast host)
+#                       ::/128      - IPv6 unspecified (all zeros; never a real peer)
+ignoreip              = 127.0.0.1/8 ::1/128 fe80::/10 ff00::/8 ::/128 MUST_BE_SET

 [recidive]
-enabled   = true
-filter    = recidive
-logpath   = /var/log/fail2ban/fail2ban.log*
-banaction = iptables-allports
-bantime   = 32d
-findtime  = 384d
-maxretry  = 4
+enabled               = true
+banaction             = ufw[blocktype=deny]
+bantime               = 8d
+bantime.increment     = true
+bantime.factor        = 1
+bantime.maxtime       = 128d
+bantime.multipliers   = 1 2 4 8 16
+bantime.overalljails  = true
+bantime.rndtime       = 877s
+filter                = recidive
+findtime              = 16d
+logpath               = /var/log/fail2ban/fail2ban.log*
+maxretry              = 3

 ### SSH Handling: Foreign IP (not in /etc/hosts.allow): refused to connect: immediate ban [sshd-refused]
 ###               Jump host mistyped 1-3 times: no ban, only after four attempts          [sshd]

 [sshd]
-enabled   = true
-backend   = systemd
-filter    = sshd
-mode      = normal
-port      = MUST_BE_SET
-protocol  = tcp
-logpath   = /var/log/auth.log
-maxretry  = 4
-findtime  = 24h
-bantime   = 24h
+enabled               = true
+backend               = systemd
+bantime               = 1h
+bantime.increment     = true
+bantime.factor        = 1
+bantime.maxtime       = 16d
+bantime.multipliers   = 1 2 4 8 16 32 64 128 256 384
+bantime.overalljails  = true
+bantime.rndtime       = 877s
+filter                = sshd
+findtime              = 16m
+maxretry              = 4
+mode                  = aggressive
+port                  = MUST_BE_SET
+protocol              = tcp

 [sshd-refused]
-enabled   = true
-filter    = ciss-sshd-refused
-port      = MUST_BE_SET
-protocol  = tcp
-logpath   = /var/log/auth.log
-maxretry  = 1
-findtime  = 24h
-bantime   = 24h
+enabled               = true
+bantime               = 1h
+bantime.increment     = true
+bantime.factor        = 1
+bantime.maxtime       = 16d
+bantime.multipliers   = 1 2 4 8 16 32 64 128 256 384
+bantime.overalljails  = true
+bantime.rndtime       = 877s
+filter                = ciss-sshd-refused
+findtime              = 16m
+logpath               = /var/log/auth.log
+maxretry              = 1
+port                  = MUST_BE_SET
+protocol              = tcp

-# ufw aggressive approach:
-# Any valid client communicating with our server should be going directly to the service ports opened in ufw (ssh, 80, 443, ...).
-# Any client touching other ports is treated as malicious and therefore should be blocked access to ALL ports after one attempt.
+#
+# CISS aggressive approach:
+# Any valid client communicating with our server should be going directly to the service ports opened in ufw (ssh, 80, ...).
+# Any client touching other ports is treated as malicious and therefore should be blocked access to ALL ports after 1 attempt.
+# There is no necessity to ping our servers excessively. Any client pinging us more than 1 times will be blocked.
+#
+
+[icmp]
+enabled               = true
+banaction             = ufw[blocktype=deny]
+bantime               = 1h
+bantime.increment     = true
+bantime.factor        = 1
+bantime.maxtime       = 16d
+bantime.multipliers   = 1 2 4 8 16 32 64 128 256 384
+bantime.overalljails  = true
+bantime.rndtime       = 877s
+filter                = ciss-icmp
+findtime              = 16m
+logpath               = /var/log/ufw.log
+maxretry              = 1

 [ufw]
-enabled   = true
-filter    = ciss-ufw
-action    = iptables-allports
-logpath   = /var/log/ufw.log
-maxretry  = 1
-bantime   = 24h
-findtime  = 24h
+enabled               = true
+banaction             = ufw[blocktype=deny]
+bantime               = 1h
+bantime.increment     = true
+bantime.factor        = 1
+bantime.maxtime       = 16d
+bantime.multipliers   = 1 2 4 8 16 32 64 128 256 384
+bantime.overalljails  = true
+bantime.rndtime       = 877s
+filter                = ciss-ufw
+findtime              = 16m
+logpath               = /var/log/ufw.log
+maxretry              = 1

 # vim: number et ts=2 sw=2 sts=2 ai tw=128 ft=conf
 EOF

-cat << 'EOF' >| /etc/fail2ban/filter.d/ciss-ufw.conf
+cat << 'EOF' >| /etc/fail2ban/filter.d/ciss-icmp.conf
 # SPDX-Version: 3.0
 # SPDX-CreationInfo: 2025-10-18; WEIDNER, Marc S.; <cendev@coresecret.eu>
 # SPDX-ExternalRef: GIT https://cendev.eu/marc.weidner/CISS.2025.debian.live.builder.git
@@ -112,7 +149,29 @@ cat << 'EOF' >| /etc/fail2ban/filter.d/ciss-ufw.conf
 # SPDX-Security-Contact: security@coresecret.eu

 [Definition]
-failregex = \[UFW BLOCK\].+SRC=<HOST> DST
+# Generic ICMP/ICMPv6 blocks
+failregex             = ^.*UFW (?:BLOCK|REJECT).*?\bSRC=<HOST>\b.*?\bPROTO=ICMP\b.*$
+                        ^.*UFW (?:BLOCK|REJECT).*?\bSRC=<HOST>\b.*?\bPROTO=ICMPv6\b.*$
+
+# vim: number et ts=2 sw=2 sts=2 ai tw=128 ft=conf
+EOF
+
+cat << EOF >| /etc/fail2ban/filter.d/ciss-ufw.conf
+# SPDX-Version: 3.0
+# SPDX-CreationInfo: 2025-10-18; WEIDNER, Marc S.; <cendev@coresecret.eu>
+# SPDX-ExternalRef: GIT https://cendev.eu/marc.weidner/CISS.2025.debian.live.builder.git
+# SPDX-FileContributor: WEIDNER, Marc S.; Centurion Intelligence Consulting Agency
+# SPDX-FileCopyrightText: 2024-2025; WEIDNER, Marc S.; <cendev@coresecret.eu>
+# SPDX-FileType: SOURCE
+# SPDX-License-Identifier: EUPL-1.2 OR LicenseRef-CCLA-1.0
+# SPDX-LicenseComment: This file is part of the CISS.debian.installer.secure framework.
+# SPDX-PackageName: CISS.debian.live.builder
+# SPDX-Security-Contact: security@coresecret.eu
+
+[Definition]
+# Match UFW BLOCK/REJECT with a source IP and *any* port field (SPT or DPT), protocol may be missing.
+failregex             = ^.*UFW (?:BLOCK|REJECT).*?\bSRC=<HOST>\b.*?(?:\bDPT=\d+\b|\bSPT=\d+\b).*$
+ignoreregex           =

 # vim: number et ts=2 sw=2 sts=2 ai tw=128 ft=conf
 EOF
@@ -169,33 +228,36 @@ EOF

 cat << 'EOF' >> /etc/fail2ban/fail2ban.local
 [Definition]
-logtarget = /var/log/fail2ban/fail2ban.log
+logtarget             = /var/log/fail2ban/fail2ban.log

 [Database]
 # Keep entries for at least 384 days to cover recidive findtime.
-dbpurgeage = 384d
+dbpurgeage            = 384d
 EOF

 ###########################################################################################
 # Remarks: Logrotate must be updated either                                               #
 ###########################################################################################
 cp -a /etc/logrotate.d/fail2ban /root/.ciss/dlb/backup/fail2ban_logrotate.bak
-#sed -i 's/\/var\/log\/fail2ban.log/\/var\/log\/fail2ban\/fail2ban.log/1' /etc/logrotate.d/fail2ban
 cat << EOF >| /etc/logrotate.d/fail2ban
 /var/log/fail2ban/fail2ban.log {
-
    daily
    rotate 384
-    compress
-    # Do not rotate if empty
+    maxage 384
    notifempty
-
+    dateext
+    dateyesterday
+    compress
+    compresscmd /usr/bin/zstd
+    compressext .zst
+    compressoptions -20
+    uncompresscmd /usr/bin/unzstd
    delaycompress
+    shred
    missingok
    postrotate
        fail2ban-client flushlogs 1>/dev/null
    endscript
-
    # If fail2ban runs as non-root it still needs to have write access
    # to logfiles.
    # create 640 fail2ban adm