Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 41 insertions, 0 deletions

diff --git a/man/tpm2-crypttab.sh b/man/tpm2-crypttab.sh
new file mode 100644
index 0000000..2be3499
--- /dev/null
+++ b/man/tpm2-crypttab.sh
@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: MIT-0
+
+# Enroll the TPM2 security chip in the LUKS2 volume, and bind it to PCR 7
+# only. Replace /dev/sdXn by the partition to use (e.g. /dev/sda1).
+sudo systemd-cryptenroll --tpm2-device=auto --tpm2-pcrs=7 /dev/sdXn
+
+# Test: Let's run systemd-cryptsetup to test if this worked.
+sudo systemd-cryptsetup attach mytest /dev/sdXn - tpm2-device=auto
+
+# If that worked, let's now add the same line persistently to /etc/crypttab,
+# for the future. We don't want to use the (unstable) /dev/sdX name, so let's
+# figure out a stable link:
+udevadm info -q -r symlink /dev/sdXn
+
+# Now add the line using the by-uuid symlink to /etc/crypttab:
+sudo bash -c 'echo "mytest /dev/disk/by-uuid/... - tpm2-device=auto" >>/etc/crypttab'
+
+# And now let's check that automatic unlocking works:
+sudo systemd-cryptsetup detach mytest
+sudo systemctl daemon-reload
+sudo systemctl start cryptsetup.target
+systemctl is-active systemd-cryptsetup@mytest.service
+
+# Once we have the device which will be unlocked automatically, we can use it.
+# Usually we would create a file system and add it to /etc/fstab:
+sudo mkfs.ext4 /dev/mapper/mytest
+# This prints a 'Filesystem UUID', which we can use as a stable name:
+sudo bash -c 'echo "/dev/disk/by-uuid/... /var/mytest ext4 defaults,x-systemd.mkdir 0 2" >>/etc/fstab'
+# And now let's check that the mounting works:
+sudo systemctl daemon-reload
+sudo systemctl start /var/mytest
+systemctl status /var/mytest
+
+# Depending on your distribution and encryption setup, you may need to manually
+# regenerate your initramfs to be able to use a TPM2 security chip to unlock
+# the partition during early boot.
+# More information at https://unix.stackexchange.com/a/705809.
+# On Fedora based systems:
+sudo dracut --force
+# On Debian based systems:
+sudo update-initramfs -u