6 Commits
0.8-1 ... 1.1-1

Author SHA1 Message Date
Julien Coloos
22da78cdef v1.1-1 2022-03-24 21:58:20 +01:00
Julien Coloos
d34b39b77f Refactored install script
Re-arrange and add comments to more easily spot code coming from other
hooks.
2022-03-24 21:52:03 +01:00
Julien Coloos
8f92d149eb Update help message after install
Show up-to-date options details.
2022-03-24 21:49:09 +01:00
Julien Coloos
f20941d376 Options to re-enable WOL and start a full shell
Adding ethtool - to allows chaning WOL settings - does not add much more
dependencies compared to the core ones (network, dropbear, cryptsetup).

Refactor script for easier maintenance.

v1.0-1
2021-11-13 21:02:49 +01:00
Julien Coloos
a2924457d3 Use SHA256 checksums instead of MD5 2021-11-13 17:00:58 +01:00
Julien Coloos
c3cafcf6cd Try to print network devices information when interface setup fails
Useful to check interfaces name and MAC address.

v0.9-1
2021-10-24 17:56:16 +02:00
6 changed files with 640 additions and 353 deletions

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@@ -1,56 +1,95 @@
2022-03-24 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v1.1-1
Refactored install script to more easily spot code coming from other
nominal hooks.
Updated install script message with latest available options.
Removed dependency to '/lib/libnss_files.so', as it does not exist and
should not be needed anymore.
Prevents unwanted warning when building initcpio
==> ERROR: file not found: `/lib/libnss_files.so'
See: https://bugs.archlinux.org/task/73702
2021-11-13 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v1.0-1
Option to use login shell instead of cryptsetup unlocking script.
Option to re-enable Wake-on-LAN on network device.
2021-11-12 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.9-2
Use SHA256 checksums instead of MD5.
2021-10-24 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.9-1
Try to print network devices information when interface setup fails.
2021-08-15 Julien Coloos <julien.coloos [at] gmail [dot] com> 2021-08-15 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.8-1 * v0.8-1
Include 'libgcc_s.so.1' which is necessary for (at least) proper LUKS v2 handling Include 'libgcc_s.so.1' which is necessary for (at least) proper LUKS
v2 handling.
2020-07-14 Julien Coloos <julien.coloos [at] gmail [dot] com> 2020-07-14 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.7-1 * v0.7-1
Dropped 'dsa' private key support; added 'ed25519' private key support Dropped 'dsa' private key support; added 'ed25519' private key support.
2018-03-13 Julien Coloos <julien.coloos [at] gmail [dot] com> 2018-03-13 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.6-1 * v0.6-1
Dropped '-m' option when calling dropbear (latest ArchLinux version does not handle it) Dropped '-m' option when calling dropbear (latest ArchLinux version
does not handle it).
2017-06-25 Julien Coloos <julien.coloos [at] gmail [dot] com> 2017-06-25 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.5-1 * v0.5-1
Fixed cryptsetup additional arguments handling: were not properly passed Fixed cryptsetup additional arguments handling: were not properly
passed.
2017-06-25 Julien Coloos <julien.coloos [at] gmail [dot] com> 2017-06-25 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.4-1 * v0.4-1
Fixed TRIM option handling in /etc/crypttab: 'discard' ('allow-discards' being the switch name to use in cryptsetup) Fixed TRIM option handling in /etc/crypttab: 'discard'
('allow-discards' being the switch name to use in cryptsetup).
2015-11-22 Julien Coloos <julien.coloos [at] gmail [dot] com> 2015-11-22 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.3-1 * v0.3-1
Added configurable timeout for ipconfig Added configurable timeout for ipconfig.
Moved configuration file from /etc/dropbear/initrd.env to /etc/initcpio/sshcs_env Moved configuration file from /etc/dropbear/initrd.env to
/etc/initcpio/sshcs_env.
2014-05-20 Julien Coloos <julien.coloos [at] gmail [dot] com> 2014-05-20 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.2-1 * v0.2-1
Removed unnecessary dependency: psmisc Removed unnecessary dependency: psmisc.
Added configurable timeout to unlock devices before automatic poweroff Added configurable timeout to unlock devices before automatic poweroff.
2014-05-19 Julien Coloos <julien.coloos [at] gmail [dot] com> 2014-05-19 Julien Coloos <julien.coloos [at] gmail [dot] com>
* v0.1-1 * v0.1-1
* Code adapted from dropbear_initrd_encrypt (https://aur.archlinux.org/packages/dropbear_initrd_encrypt/) Code adapted from dropbear_initrd_encrypt.
Reworked code See: https://aur.archlinux.org/packages/dropbear_initrd_encrypt/
Dropped non-LUKS support
Rely on /etc/crypttab
Handle multiple devices to unlock
Merged dropbear and encryptssh hooks
Better resources cleanup
Reworked code.
Dropped non-LUKS support.
Rely on /etc/crypttab.
Handle multiple devices to unlock.
Merged dropbear and encryptssh hooks.
Better resources cleanup.

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@@ -1,20 +1,21 @@
# Maintainer: Julien Coloos <julien.coloos [at] gmail [dot] com> # Maintainer: Julien Coloos <julien.coloos [at] gmail [dot] com>
pkgname=initrd-ssh-cryptsetup pkgname=initrd-ssh-cryptsetup
pkgver=0.8 pkgver=1.1
pkgrel=1 pkgrel=1
pkgdesc="Allows for LUKS-encrypted devices to be unlocked remotely over SSH" pkgdesc="Allows to remotely unlock LUKS-encrypted devices over SSH"
arch=('any') arch=('any')
url="https://github.com/suiryc/archlinux-$pkgname" url="https://github.com/suiryc/archlinux-$pkgname"
license=('GPL3') license=('GPL3')
depends=('dropbear' 'cryptsetup' 'mkinitcpio-nfs-utils' 'iproute2') depends=('dropbear' 'cryptsetup' 'mkinitcpio-nfs-utils' 'iproute2' 'ethtool')
install=$pkgname.install install=$pkgname.install
changelog='ChangeLog' changelog='ChangeLog'
source=("http://julien.coloos.free.fr/archlinux/$pkgname-$pkgver.tar.xz" "$pkgname.install") source=("http://julien.coloos.free.fr/archlinux/$pkgname-$pkgver.tar.xz" "$pkgname.install")
md5sums=('ac5a53fbc288ccce61874488bcbbf58a' sha256sums=('33295d11216cb96a5b30f035add123d136fac38decd393d677f1c02b9ad22379'
'ac60109d80e7bb2af0d66e69aaf178a6') 'b84978b3c2ef32208c2b104ee2d3ce8aaec26da0bd4e9e1c83942f373bbf6285')
package() { package() {
install -Dm644 "$srcdir/src/install/ssh-cryptsetup" "$pkgdir/usr/lib/initcpio/install/ssh-cryptsetup" install -Dm644 "$srcdir/src/install/ssh-cryptsetup" "$pkgdir/usr/lib/initcpio/install/ssh-cryptsetup"
install -Dm644 "$srcdir/src/hooks/ssh-cryptsetup" "$pkgdir/usr/lib/initcpio/hooks/ssh-cryptsetup" install -Dm644 "$srcdir/src/hooks/ssh-cryptsetup" "$pkgdir/usr/lib/initcpio/hooks/ssh-cryptsetup"
install -Dm644 "$srcdir/src/hooks/ssh-cryptsetup-tools" "$pkgdir/usr/lib/initcpio/hooks/ssh-cryptsetup-tools"
} }

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@@ -1,4 +1,4 @@
Personal ArchLinux package combining dropbear and cryptsetup in initrd for unlocking LUKS-encrypted devices either locally (boot console) or remotely over SSH. Personal ArchLinux package combining dropbear and cryptsetup in initramfs for unlocking LUKS-encrypted devices either locally (boot console) or remotely over SSH.
The code was reworked from legacy dropbear_initrd_encrypt AUR package. The code was reworked from legacy dropbear_initrd_encrypt AUR package.
@@ -30,38 +30,50 @@ As explained upon installation, the following things need to be done:
* add the authorized SSH public key to `/etc/dropbear/initrd.authorized_keys` * add the authorized SSH public key to `/etc/dropbear/initrd.authorized_keys`
* add the `ip=` kernel command parameter to the bootloader configuration (see https://wiki.archlinux.org/index.php/Mkinitcpio#Using_net) * add the `ip=` kernel command parameter to the bootloader configuration (see https://wiki.archlinux.org/index.php/Mkinitcpio#Using_net)
- e.g. with `grub`: add `ip=:::::eth0:dhcp` to `GRUB_CMDLINE_LINUX_DEFAULT` in `/etc/default/grub`, and re-generate the configuration with `grub-mkconfig -o /boot/grub/grub.cfg` - e.g. with `grub`: add `ip=:::::eth0:dhcp` to `GRUB_CMDLINE_LINUX_DEFAULT` in `/etc/default/grub`, and re-generate the configuration with `grub-mkconfig -o /boot/grub/grub.cfg`
- also see https://git.kernel.org/pub/scm/libs/klibc/klibc.git/tree/usr/kinit/ipconfig/README.ipconfig
* in the `HOOKS` section of `/etc/mkinitcpio.conf`, add `ssh-cryptsetup` before `filesystems`; then rebuild the initramfs: `mkinitcpio -p linux` * in the `HOOKS` section of `/etc/mkinitcpio.conf`, add `ssh-cryptsetup` before `filesystems`; then rebuild the initramfs: `mkinitcpio -p linux`
- when using a non-standard keyboard layout, it is also useful to add the `keymap` hook before `ssh-cryptsetup`, and also move `keyboard` before `keymap` - when using a non-standard keyboard layout, it is also useful to add the `keymap` hook before `ssh-cryptsetup`, and also move `keyboard` before `keymap`
The LUKS-encrypted devices to unlock are derived from `/etc/crypttab`. The LUKS-encrypted devices to unlock are derived from `/etc/crypttab`.
Some options can be set in `/etc/initcpio/sshcs_env` (file is sourced in initrd shell): Some options can be set in `/etc/initcpio/sshcs_env` (file is sourced in initramfs shell):
* `sshcs_opt_debug`: whether to be more verbose about ongoing actions * `sshcs_opt_debug`: whether to be more verbose about ongoing actions
- default: 0 - default: `0`
- any non-zero value to enable - any non-zero value to enable
* `sshcs_opt_net_wol`: Wake-on-LAN option to set on network device
- default: `g` (MagicPacket™)
- usually WOL is disabled once in initramfs shell
- set empty to not change network device WOL setting
* `sshcs_opt_timeout_ipconfig`: time (in seconds) to configure IP * `sshcs_opt_timeout_ipconfig`: time (in seconds) to configure IP
- default: 10 seconds - default: `10`
* `sshcs_opt_listen`: SSH listening port * `sshcs_opt_listen`: SSH listening port
- default: 22 - default: `22`
* `sshcs_opt_timeout_poweroff`: time (in seconds) to unlock devices before automatic powering off * `sshcs_opt_timeout_poweroff`: time (in seconds) to unlock devices before automatic powering off
- default (and minimum value): 2 minutes - default (and minimum value): `120` (2 minutes)
- negative value to deactivate - negative value to deactivate
* `sshcs_opt_use_shell`: whether to start a full `ash` shell
- default: `0`
- `1` to enable
- when disabled (the default), a script to unlock devices is executed instead
For example: For example:
sshcs_opt_timeout_ipconfig=30 sshcs_opt_timeout_ipconfig=30
sshcs_opt_listen=2222 sshcs_opt_listen=2222
sshcs_opt_timeout_poweroff=-1 sshcs_opt_timeout_poweroff=-1
sshcs_opt_use_shell=1
## Building notes ## Building notes
1. Modify the sources (features in `src`, and/or package building files) 1. Modify the sources (features in `src`, and/or package building files)
2. If `src` was modified 2. If `src` was modified
* archive the `src` folder in `$pkgname-$pkgver.tar.xz` file; e.g.: `tar -cJf initrd-ssh-cryptsetup-0.7.tar.xz src` * bump `pkgver` in `PKGBUILD`
* archive the `src` folder in `$pkgname-$pkgver.tar.xz` file; e.g.: `tar -cJf initrd-ssh-cryptsetup-$(grep "^pkgver=" PKGBUILD | cut -d'=' -f2).tar.xz src`
* upload the archive on the online repository (pointed by `PKGBUILD`) * upload the archive on the online repository (pointed by `PKGBUILD`)
3. Update ChangeLog 3. Update ChangeLog
4. Update `PKGBUILD` 4. Update `PKGBUILD`
* bump `pkgver` if `src` was modified, or `pkgrel` if building files were modified * bump `pkgrel` if only building files were modified
* refresh `md5sums` if necessary (based on `md5sum initrd-ssh-cryptsetup-*.tar.xz initrd-ssh-cryptsetup.install` output) * refresh `sha256sums` with `updpkgsums` if necessary
- or manually, based on `sha256sum initrd-ssh-cryptsetup-*.tar.xz initrd-ssh-cryptsetup.install` output
5. Delete generated archive file if any 5. Delete generated archive file if any

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@@ -1,308 +1,324 @@
#!/usr/bin/ash #!/usr/bin/ash
dbg () { . "/usr/local/bin/ssh-cryptsetup-tools"
[ ${sshcs_opt_debug} != 0 ] && echo "$@"
}
sshcs_env_load() {
local debug_default=0
local timeout_ipconfig_default=10
local timeout_poweroff_min=120
[ -e "${sshcs_env}" ] && . "${sshcs_env}"
[ -z "${sshcs_opt_debug}" ] && sshcs_opt_debug=${debug_default}
[ -z "${sshcs_opt_timeout_ipconfig}" ] && sshcs_opt_timeout_ipconfig=${timeout_ipconfig_default}
[ -n "${sshcs_opt_listen}" ] && sshcs_opt_listen="-p ${sshcs_opt_listen}"
[ -z "${sshcs_opt_timeout_poweroff}" ] && sshcs_opt_timeout_poweroff=${timeout_poweroff_min}
[ ${sshcs_opt_timeout_poweroff} -ge 0 ] && [ ${sshcs_opt_timeout_poweroff} -lt ${timeout_poweroff_min} ] && sshcs_opt_timeout_poweroff=${timeout_poweroff_min}
}
sshcs_net_start() { sshcs_net_start() {
# we must have an 'ip' setting, and a device in it local iparg net_address ipconfig_out net_netmask net_gateway net_dns0 net_dns1
[ -z "${ip}" ] && [ -n "${nfsaddrs}" ] && ip="${nfsaddrs}"
[ -z "${ip}" ] && {
dbg "No ip setting to setup network"
return 1
}
net_device=$(echo ${ip} | cut -d: -f6) # we must have an 'ip' setting, and a device in it
[ -z "${net_device}" ] && { [ -z "${ip}" ] && [ -n "${nfsaddrs}" ] && ip="${nfsaddrs}"
dbg "No network device to setup" [ -z "${ip}" ] && {
return 1 dbg "No ip setting to setup network"
} return 1
}
# Setup network and save some values net_device=$(echo ${ip} | cut -d: -f6)
# Note: some useful redirection means ('< <(...)' and '<<< "$(...)"') are [ -z "${net_device}" ] && {
# not supported in the available shell. So we have to write code in a dbg "No network device to setup"
# temporary file and 'source' it since '... | while read ...' spawns a return 1
# subshell from which outer variables cannot be altered. }
: > "${net_env}"
echo "" if [ "${sshcs_opt_net_wol:-d}" != "d" ]; then
echo "Configuring IP (timeout = ${sshcs_opt_timeout_ipconfig}s) ..." dbg "Setting network device=${net_device} wol=${sshcs_opt_net_wol}"
ipconfig_out=$(ipconfig -t "${sshcs_opt_timeout_ipconfig}" "ip=${ip}") ethtool -s "${net_device}" wol "${sshcs_opt_net_wol}"
if [ $? -ne 0 ]; then fi
err "IP configuration timeout!"
return 1
fi
echo -n "${ipconfig_out}" | while read line; do # Setup network and save some values
[ "${line#"IP-Config:"}" != "${line}" ] && continue # Note: some useful redirection means ('< <(...)' and '<<< "$(...)"') are
# not supported in the available shell. So we have to write code in a
# temporary file and 'source' it since '... | while read ...' spawns a
# subshell from which outer variables cannot be altered.
: > "${net_env}"
line="$(echo "${line}" | sed -e 's/ :/:/g;s/: /=/g')" echo ""
echo "Configuring IP (timeout = ${sshcs_opt_timeout_ipconfig}s) ..."
# ipconfig manual: https://git.kernel.org/pub/scm/libs/klibc/klibc.git/tree/usr/kinit/ipconfig/README.ipconfig
ipconfig_out=$(ipconfig -t "${sshcs_opt_timeout_ipconfig}" "ip=${ip}")
if [ $? -ne 0 ]; then
err "IP configuration timeout!"
echo "Devices probing:"
ipconfig -n -t 5 -c none all
return 1
fi
for iparg in ${line}; do echo -n "${ipconfig_out}" | while read line; do
case "${iparg}" in [ "${line#"IP-Config:"}" != "${line}" ] && continue
address=*|netmask=*|gateway=*|dns0=*|dns1=*)
echo "net_${iparg}" >> "${net_env}" line="$(echo "${line}" | sed -e 's/ :/:/g;s/: /=/g')"
;;
esac for iparg in ${line}; do
done case "${iparg}" in
address=*|netmask=*|gateway=*|dns0=*|dns1=*)
echo "net_${iparg}" >> "${net_env}"
;;
esac
done done
done
. "${net_env}" . "${net_env}"
rm -f "${net_env}" rm -f "${net_env}"
echo "IP-Config: device=${net_device} ip=${net_address}/${net_netmask} gw=${net_gateway} dns0=${net_dns0} dns1=${net_dns1}" echo "IP-Config: device=${net_device} ip=${net_address}/${net_netmask} gw=${net_gateway} dns0=${net_dns0} dns1=${net_dns1}"
[ -n "${net_address}" ] [ -n "${net_address}" ]
} }
sshcs_net_done() { sshcs_net_done() {
# we are done with the network # we are done with the network
if [ -n "${net_device}" ]; then if [ -n "${net_device}" ]; then
dbg "Setting network device=${net_device} down" dbg "Setting network device=${net_device} down"
ip addr flush dev "${net_device}" ip addr flush dev "${net_device}"
ip link set dev "${net_device}" down ip link set dev "${net_device}" down
fi fi
} }
sshcs_trapped_timeout() { sshcs_trapped_timeout() {
err "Timeout reached! Powering off." err "Timeout reached! Powering off."
poweroff -f poweroff -f
exit exit
} }
sshcs_trap_timeout() { sshcs_trap_timeout() {
local pid_init=$$ local pid_init=$$
if [ ${sshcs_opt_timeout_poweroff} -gt 0 ]; then if [ ${sshcs_opt_timeout_poweroff} -gt 0 ]; then
echo "" echo ""
echo "WARNING! Automatic poweroff will be triggered in ${sshcs_opt_timeout_poweroff}s" echo "WARNING! Automatic poweroff will be triggered in ${sshcs_opt_timeout_poweroff}s"
echo "To deactivate, please unlock devices" echo "To deactivate, please unlock devices"
echo "" trap sshcs_trapped_timeout SIGALRM
trap sshcs_trapped_timeout SIGALRM (
( sleep ${sshcs_opt_timeout_poweroff}
sleep ${sshcs_opt_timeout_poweroff} kill -SIGALRM ${pid_init}
kill -SIGALRM ${pid_init} # Signal is not processed if cryptsetup is waiting for the password
# Signal is not processed if cryptsetup is waiting for the password killall cryptsetup > /dev/null 2>&1
killall cryptsetup > /dev/null 2>&1 ) &
) & pid_timeout=$!
pid_timeout=$! fi
fi
} }
sshcs_untrap_timeout() { sshcs_untrap_timeout() {
[ -z "${pid_timeout}" ] && return 0 [ -z "${pid_timeout}" ] && return 0
kill ${pid_timeout} # Notes:
trap - SIGALRM # If there was a running SSH shell, it may also try to kill it.
msg "Timeout cleared." # This only kills the spawned subshell, leaving the 'sleep' command still
# running until done (which is not an issue).
proc_parse_stat ${pid_timeout} && kill ${pid_timeout}
pid_timeout=
trap - SIGALRM
msg "Timeout cleared."
} }
sshcs_unlock() { sshcs_shell_run() {
sshcs_trap_timeout sshcs_trap_timeout
# actual script (shared with SSH login) unlocking encrypted devices # actual script (shared with SSH login) with which we can unlock devices
. "${sshcs_cryptsetup_script}" sshcs_unlocked_test=0
. "${sshcs_shell_script}"
sshcs_untrap_timeout
} }
sshcs_dropbear_unlock() { sshcs_dropbear_run() {
local pid_timeout= local pid_timeout=
local dev_pts_mounted=0 local dev_pts_mounted=0
local listen= local listen=
# ensure /dev/pts is present # ensure /dev/pts is present
if [ ! -d "/dev/pts" ]; then if [ ! -d "/dev/pts" ]; then
mkdir -p "/dev/pts" mkdir -p "/dev/pts"
mount -t devpts devpts "/dev/pts" mount -t devpts devpts "/dev/pts"
dev_pts_mounted=1 dev_pts_mounted=1
fi fi
# /etc/passwd file for the root user if [ ${sshcs_opt_use_shell} -eq 0 ]; then
echo "root:x:0:0:root:/root:${dropbear_login_shell}" > "/etc/passwd" sshcs_shell_script=${sshcs_cryptsetup_script}
echo "${dropbear_login_shell}" > "/etc/shells" else
cat <<EOF > "${sshcs_shell_script}"
# root login script
cat <<EOF > "${dropbear_login_shell}"
#!/usr/bin/ash #!/usr/bin/ash
. "/init_functions" . "/usr/local/bin/ssh-cryptsetup-tools"
if [ ! -f "${sshcs_cryptsetup_script}" ]; then
err "No cryptsetup script present! Please retry."
exit 0
fi
if [ -c "/dev/mapper/control" ]; then
CSQUIET=
. "${sshcs_cryptsetup_script}"
echo ""
echo "cryptsetup succeeded! Boot sequence should go on."
echo "Please wait and retry for standard SSH service."
else
err "Device resources missing! Please retry."
fi
echo "" echo ""
echo "Call ${sshcs_cryptsetup_script} to try unlocking device(s)"
# Now give the user its shell
/usr/bin/ash
# Check whether we are fully done
sshcs_check_done 1
EOF EOF
chmod a+x "${dropbear_login_shell}" chmod a+x "${sshcs_shell_script}"
fi
[ ! -d "/var/log" ] && mkdir -p "/var/log" # /etc/passwd file for the root user
touch "/var/log/lastlog" echo "root:x:0:0:root:/root:${sshcs_shell_script}" > "/etc/passwd"
echo "${sshcs_shell_script}" > "/etc/shells"
msg "Starting dropbear ..." [ ! -d "/var/log" ] && mkdir -p "/var/log"
dropbear -Esgjk -P "${path_dropbear_pid}" ${sshcs_opt_listen} touch "/var/log/lastlog"
# Actual unlocking msg "Starting dropbear ..."
sshcs_unlock dropbear -Esgjk -P "${path_dropbear_pid}" ${sshcs_opt_listen}
# cleanup dropbear # Actual unlocking shell
if [ -f "${path_dropbear_pid}" ]; then sshcs_shell_run
msg "Stopping dropbear ..."
kill $(cat "${path_dropbear_pid}")
rm -f "${path_dropbear_pid}"
fi
rm -f "${sshcs_cryptsetup_script}" "${dropbear_login_shell}" "/etc/passwd" "/etc/shells" "/var/log/lastlog"
# cleanup /dev/pts if necessary
if [ ${dev_pts_mounted} -ne 0 ]; then
umount "/dev/pts"
rm -R "/dev/pts"
fi
} }
sshcs_cryptpart_process() { sshcs_cryptpart_process() {
# ensure there is a device (handle 'UUID=' format) local cryptdev_orig cryptopt cryptargs
[ -z "${cryptdev}" ] && return 0
[ "${cryptdev#UUID=}" != "${cryptdev}" ] && cryptdev="/dev/disk/by-uuid/${cryptdev#UUID=}"
# get crypt options # ensure there is a device (handle 'UUID=' format)
cryptargs= [ -z "${cryptdev}" ] && return 0
for cryptopt in ${cryptoptions//,/ }; do [ "${cryptdev#UUID=}" != "${cryptdev}" ] && cryptdev="/dev/disk/by-uuid/${cryptdev#UUID=}"
case ${cryptopt} in
discard)
cryptargs="${cryptargs} --allow-discards"
;;
luks) # get crypt options
;; cryptargs=
for cryptopt in ${cryptoptions//,/ }; do
case ${cryptopt} in
discard)
cryptargs="${cryptargs} --allow-discards"
;;
*) luks)
echo "Device ${cryptdev} encryption option '${cryptopt}' not known, ignoring." ;;
;;
esac
done
# ensure device is encrypted and handled *)
cryptdev_orig=${cryptdev} echo "Device ${cryptdev} encryption option '${cryptopt}' not known, ignoring."
if cryptdev=$(resolve_device "${cryptdev_orig}" ${rootdelay}); then ;;
if cryptsetup isLuks "${cryptdev}" >/dev/null 2>&1; then esac
dbg "Adding crypt device=${cryptdev} type=${crypttype} name=${cryptname} args=<${cryptargs}> in setup script" done
# ensure device is encrypted and handled
cryptdev_orig=${cryptdev}
if cryptdev=$(resolve_device "${cryptdev_orig}" ${rootdelay}); then
if cryptsetup isLuks "${cryptdev}" >/dev/null 2>&1; then
dbg "Adding crypt device=${cryptdev} type=${crypttype} name=${cryptname} args=<${cryptargs}> in setup script"
# update script used to unlock device either in console or SSH
[ -s "${sshcs_cryptsetup_script}" ] || cat <<'EOF' > "${sshcs_cryptsetup_script}"
#!/usr/bin/ash
. "/usr/local/bin/ssh-cryptsetup-tools"
# update script used to unlock device either in console or SSH
[ -s "${sshcs_cryptsetup_script}" ] || cat <<EOF > "${sshcs_cryptsetup_script}"
cycle_or_retry() { cycle_or_retry() {
local res local res
read -n 1 -s -t 5 -p "Whithin 5s press 'P' to poweroff, 'R' to reboot or any other key to retry. " res read -n 1 -s -t 5 -p "Within 5s press 'P' to poweroff, 'R' to reboot or any other key to retry. " res
echo "" echo ""
if [ "\${res}" = "P" ]; then [ "${res}" == "P" ] && poweroff -f
poweroff -f [ "${res}" == "R" ] && reboot -f
elif [ "\${res}" = "R" ]; then
reboot -f
fi
} }
try_unlock() {
EOF EOF
cat <<EOF >> "${sshcs_cryptsetup_script}" cat <<EOF >> "${sshcs_cryptsetup_script}"
# loop until device is available # loop until device is available
while [ ! -e "/dev/mapper/${cryptname}" ]; do while [ ! -e "/dev/mapper/${cryptname}" ]; do
if [ \${sshcs_unlocked_test:-0} -eq 1 ]; then
sshcs_unlocked=0
return
fi
if cryptsetup open --type "${crypttype}" "${cryptdev}" "${cryptname}" ${cryptargs} "\${CSQUIET}"; then if cryptsetup open --type "${crypttype}" "${cryptdev}" "${cryptname}" ${cryptargs} "\${CSQUIET}"; then
if poll_device "/dev/mapper/${cryptname}" ${rootdelay}; then if poll_device "/dev/mapper/${cryptname}" ${rootdelay}; then
killall cryptsetup > /dev/null 2>&1 killall cryptsetup > /dev/null 2>&1
break
fi
err "Device still not mapped! Please wait or retry."
elif [ ! -e "/dev/mapper/${cryptname}" ]; then
err "cryptsetup failed! Please retry."
else
break break
fi
err "Device still not mapped! Please wait or retry."
elif [ ! -e "/dev/mapper/${cryptname}" ]; then
err "cryptsetup failed! Please retry."
else
break
fi fi
cycle_or_retry cycle_or_retry
done done
EOF EOF
else else
err "Failed to manage encrypted device ${cryptdev_orig}: not a LUKS volume." err "Failed to manage encrypted device ${cryptdev_orig}: not a LUKS volume."
fi
fi fi
fi
}
sshcs_cryptpart_setup() {
local cryptdev crypttype cryptname cryptpass cryptoptions
# check encrypted devices to handle
cryptdev=
crypttype=luks
while read cryptname cryptdev cryptpass cryptoptions; do
# skip comment lines
[ "${cryptname:0:1}" = "#" ] && continue
# skip devices with given password
[ -n "${cryptpass}" ] && [ "${cryptpass}" != "none" ] && [ "${cryptpass}" != "-" ] && continue
sshcs_cryptpart_process
done < "${etc_crypttab}"
# Nothing else to do if there is no device we can unlock
[ -s "${sshcs_cryptsetup_script}" ] || return 0
cat <<'EOF' >> "${sshcs_cryptsetup_script}"
# No other device to unlock
}
if [ -c "/dev/mapper/control" ]; then
CSQUIET=
try_unlock
[ ${sshcs_unlocked_test:-0} -eq 1 ] && return
sshcs_check_done 0
else
if [ \${sshcs_unlocked_test:-0} -eq 1 ]; then
sshcs_unlocked=0
return
fi
echo ""
err "Device resources missing! Please retry."
fi
EOF
chmod a+x "${sshcs_cryptsetup_script}"
} }
run_hook() { run_hook() {
local etc_crypttab="/etc/crypttab" local etc_crypttab="/etc/crypttab"
local sshcs_env="/etc/initcpio/sshcs_env" local path_dropbear_pid="/.dropbear.pid"
local path_dropbear_pid="/.dropbear.pid" local sshcs_shell_script="/.sshcs_shell.sh"
local dropbear_login_shell="/.cryptsetup_shell.sh" local net_env="/.sshcs_net_env.sh"
local sshcs_cryptsetup_script="/.cryptsetup_script.sh" local line net_device
local net_env="/.net_env.sh" local CSQUIET
local line iparg net_address net_device ipconfig_out net_netmask net_gateway net_dns0 net_dns1
local cryptdev cryptdev_orig crypttype cryptname cryptpass cryptoptions cryptopt cryptargs CSQUIET
# Load our options # Note: options were loaded already
sshcs_env_load
# sanity check: crypttab should be present # sanity check: crypttab should be present
[ ! -e "${etc_crypttab}" ] && { [ ! -e "${etc_crypttab}" ] && {
dbg "No crypttab configuration to process" dbg "No crypttab configuration to process"
return 0 return 0
} }
modprobe -a -q dm-crypt >/dev/null 2>&1 # Initialize random generator ASAP.
[ "${quiet}" = "y" ] && CSQUIET=">/dev/null" # May delay first SSH login by a few seconds otherwise.
(dd if=/dev/urandom of=/dev/null bs=4 count=1 status=none > /dev/null 2>&1) &
(dd if=/dev/random of=/dev/null bs=4 count=1 status=none > /dev/null 2>&1) &
umask 0022 modprobe -a -q dm-crypt >/dev/null 2>&1
[ "${quiet}" = "y" ] && CSQUIET=">/dev/null"
# check encrypted devices to handle umask 0022
cryptdev=
crypttype=luks
while read cryptname cryptdev cryptpass cryptoptions; do
# skip comment lines
[ "${cryptname:0:1}" = "#" ] && continue
# skip devices with given password
[ -n "${cryptpass}" ] && [ "${cryptpass}" != "none" ] && [ "${cryptpass}" != "-" ] && continue
sshcs_cryptpart_process # Setup script used to unlock device either in console or SSH
done < "${etc_crypttab}" sshcs_cryptpart_setup
if [ ! -e "${sshcs_cryptsetup_script}" ]; then
err "No encrypted device found! Skipping crypt remote unlocking."
return 0
fi
if [ ! -e "${sshcs_cryptsetup_script}" ]; then # start and check network
err "No encrypted device found! Skipping crypt remote unlocking." if ! sshcs_net_start; then
return 0 err "Net interface not available! Skipping crypt remote unlocking."
fi # We still allow to unlock locally with timeout
sshcs_shell_run
return 0
fi
# start and check network # time to unlock (through console or dropbear)
if ! sshcs_net_start; then sshcs_dropbear_run
err "Net interface not available! Skipping crypt remote unlocking."
# We still allow to unlock locally with timeout
sshcs_unlock
# stop the network if possible
sshcs_net_done
return 0
fi
# time to unlock (through console or dropbear)
sshcs_dropbear_unlock
# stop the network before going on in boot sequence
sshcs_net_done
} }

View File

@@ -0,0 +1,188 @@
#!/usr/bin/ash
. "/init_functions"
dbg () {
[ ${sshcs_opt_debug} != 0 ] && echo "$@"
}
sshcs_env_load() {
local sshcs_env="/etc/initcpio/sshcs_env"
local debug_default=0
local net_wol_default=g
local timeout_ipconfig_default=10
local timeout_poweroff_min=120
local use_shell_default=0
[ ${sshcs_env_loaded:-0} -eq 1 ] && return
[ -e "${sshcs_env}" ] && . "${sshcs_env}"
sshcs_env_loaded=1
[ -z "${sshcs_opt_debug}" ] && sshcs_opt_debug=${debug_default}
[ -z "${sshcs_opt_net_wol}" ] && sshcs_opt_net_wol=${net_wol_default}
[ -z "${sshcs_opt_timeout_ipconfig}" ] && sshcs_opt_timeout_ipconfig=${timeout_ipconfig_default}
[ -n "${sshcs_opt_listen}" ] && sshcs_opt_listen="-p ${sshcs_opt_listen}"
[ -z "${sshcs_opt_timeout_poweroff}" ] && sshcs_opt_timeout_poweroff=${timeout_poweroff_min}
[ -z "${sshcs_opt_use_shell}" ] && sshcs_opt_use_shell=${use_shell_default}
[ ${sshcs_opt_timeout_poweroff} -ge 0 ] && [ ${sshcs_opt_timeout_poweroff} -lt ${timeout_poweroff_min} ] && sshcs_opt_timeout_poweroff=${timeout_poweroff_min}
sshcs_cryptsetup_script="/.sshcs_cryptsetup_script.sh"
}
proc_parse_stat() {
local unused
pid=$1
cmd=
ppid=
[ ! -e /proc/${pid}/stat ] && return 1
read unused cmd unused ppid unused < /proc/${pid}/stat
}
proc_find_parent_cmd() {
pid=$1
proc_parse_stat ${pid} || return 1
while [ ${ppid} -gt 1 ]
do
proc_parse_stat ${ppid} || return 1
if [ "${cmd}" == "($2)" ]; then
ppid=${pid}
pid=$1
return 0
fi
pid=${ppid}
done
return 1
}
proc_is_console() {
if [ -z "${is_console:-}" ]; then
# We are in console if we were not forked from dropbear.
is_console=1
proc_find_parent_cmd $$ "dropbear" && is_console=0
fi
[ "${is_console}" -eq 1 ]
}
sshcs_cleanup() {
local pgrep_output
# Reminders:
# We are called when devices have been unlocked.
#
# We are only called as part of the main shell (whether on console - the init
# script - or through SSH - as the user login shell), and once we return our
# parent shell will end.
#
# The unlocking script does 'killall cryptsetup' after each successful unlock,
# which is used to wakeup any other running unlocking script.
# Thus as long as all devices have been unlocked, we don't expect any script
# to be stuck on 'cryptsetup' calls.
if proc_is_console; then
# We are in the console.
# It is time to properly end the processes we started and files we created.
# When using a shell - instead of directly calling the unlocking script -
# we also need to signal any SSH shell so that it is properly cleaned too.
# cleanup dropbear
if [ -f "${path_dropbear_pid}" ]; then
msg "Stopping dropbear ..."
kill $(cat "${path_dropbear_pid}")
rm -f "${path_dropbear_pid}"
fi
if [ ${sshcs_opt_use_shell} -eq 1 ]; then
# Find and kill all shells spawned by SSH.
# This is necessary to properly terminate both these shells and the spawned
# SSH processes.
# Reminder: "... | ..." does fork a subshell
dbg "Searching SSH shells ..."
pgrep_output=$(pgrep /usr/bin/ash)
pgrep_output=$(echo "${pgrep_output}" | grep -E -v "^(|1|$$)$")
echo "${pgrep_output}" | while read pid; do
proc_parse_stat ${pid} || continue
proc_find_parent_cmd ${pid} "dropbear" || continue
dbg "Killing SSH shell pid=${pid}"
kill -SIGHUP ${pid}
done
fi
# cleanup /dev/pts if necessary
if [ ${dev_pts_mounted} -ne 0 ]; then
umount "/dev/pts"
rm -R "/dev/pts"
fi
# stop the network before going on in boot sequence
sshcs_net_done
rm -f "${sshcs_cryptsetup_script}" "${sshcs_shell_script}" "/etc/passwd" "/etc/shells" "/var/log/lastlog"
elif [ ${sshcs_opt_use_shell} -eq 1 ]; then
# We are in a SSH shell session.
# Find and kill console shell.
# This is necessary so that our script launched from the init process can
# finally check that devices have been properly unlocked, properly end and
# let the init process end booting.
# Note: as a side effect, this will also kill the shell that was forked to
# trigger a timeout, which is fine (we want to kill it, either from here or
# from the init shell).
dbg "Searching console shells ..."
pgrep_output=$(pgrep /usr/bin/ash)
pgrep_output=$(echo "${pgrep_output}" | grep -E -v "^(|1|$$)$")
echo "${pgrep_output}" | while read pid; do
proc_find_parent_cmd ${pid} "dropbear" && continue
dbg "Killing console shell pid=${pid}"
kill -SIGHUP ${pid}
done
fi
# else: when in SSH shell script, we have nothing else to do other than exit.
}
sshcs_check_done() {
# Whether we are called from the main script: that is whether the shell will
# end when we return.
local finalize=$1
# This is always the main script when not using shell
[ ${sshcs_opt_use_shell} -eq 0 ] && finalize=1
# Reset timeout when applicable: only possible from init script.
proc_is_console && type sshcs_untrap_timeout > /dev/null 2>&1 && sshcs_untrap_timeout
# Check devices are unlocked.
sshcs_unlocked_test=1
sshcs_unlocked=1
. "${sshcs_cryptsetup_script}"
if [ ${sshcs_unlocked} -ne 1 ]; then
echo ""
# When finalizing in console, power off
if [ ${finalize} -eq 1 ] && proc_is_console; then
err "Devices are still locked! Powering off."
poweroff -f
fi
# When in shell or SSH, let user try again
err "Devices are still locked! Please retry."
return
fi
if [ ${finalize} -eq 0 ]; then
# Kill our parent (the interactive shell); the script that launched it will
# do finalization.
proc_parse_stat $$
kill -SIGHUP ${ppid}
exit 0
fi
echo ""
echo "cryptsetup succeeded! Boot sequence should go on."
proc_is_console || echo "Please wait and reconnect to nominal SSH service."
sshcs_cleanup
}
sshcs_env_load

View File

@@ -1,109 +1,128 @@
#!/bin/bash #!/bin/bash
sshcs_check_nonempty() { sshcs_check_nonempty() {
local filepath="$1" local filepath="$1"
[ -e "${filepath}" ] && grep -q -v '^\s*\(#\|$\)' "${filepath}" [ -e "${filepath}" ] && grep -q -v '^\s*\(#\|$\)' "${filepath}"
} }
sshcs_check_keys() { sshcs_check_keys() {
local dropbear_keyfile local dropbear_keyfile
local openssh_keyfile local openssh_keyfile
local fingerprint local fingerprint
for keytype in "${dropbear_key_types[@]}"; do for keytype in "${dropbear_key_types[@]}"; do
dropbear_keyfile=${dropbear_keyfile_prefix}${keytype}${dropbear_keyfile_suffix} dropbear_keyfile=${dropbear_keyfile_prefix}${keytype}${dropbear_keyfile_suffix}
openssh_keyfile=${openssh_keyfile_prefix}${keytype}${openssh_keyfile_suffix} openssh_keyfile=${openssh_keyfile_prefix}${keytype}${openssh_keyfile_suffix}
# Prefer OpenSSH keys, or generate missing ones # Prefer OpenSSH keys, or generate missing ones
if [ -e "${openssh_keyfile}" ]; then if [ -e "${openssh_keyfile}" ]; then
#echo "Copying OpenSSH ${keytype} host key for dropbear ..." #echo "Copying OpenSSH ${keytype} host key for dropbear ..."
dropbearconvert openssh dropbear "${openssh_keyfile}" "${dropbear_keyfile}" > /dev/null 2>&1 dropbearconvert openssh dropbear "${openssh_keyfile}" "${dropbear_keyfile}" > /dev/null 2>&1
elif [ ! -e "${dropbear_keyfile}" ]; then elif [ ! -e "${dropbear_keyfile}" ]; then
#echo "Generating ${keytype} host key for dropbear ..." #echo "Generating ${keytype} host key for dropbear ..."
dropbearkey -t "${keytype}" -f "${dropbear_keyfile}" > /dev/null 2>&1 dropbearkey -t "${keytype}" -f "${dropbear_keyfile}" > /dev/null 2>&1
fi fi
fingerprint=$(dropbearkey -y -f "${dropbear_keyfile}" | sed -n '/^Fingerprint:/ {s/Fingerprint: *//; p}') fingerprint=$(dropbearkey -y -f "${dropbear_keyfile}" | sed -n '/^Fingerprint:/ {s/Fingerprint: *//; p}')
echo "$(basename "${dropbear_keyfile}") : ${fingerprint}" echo "$(basename "${dropbear_keyfile}") : ${fingerprint}"
done done
} }
build() { build() {
local etc_crypttab="/etc/crypttab" local etc_crypttab="/etc/crypttab"
local dropbear_authorized_keys="/etc/dropbear/initrd.authorized_keys" local dropbear_authorized_keys="/etc/dropbear/initrd.authorized_keys"
local sshcs_env="/etc/initcpio/sshcs_env" local sshcs_env="/etc/initcpio/sshcs_env"
local dropbear_key_types=( "rsa" "ecdsa" "ed25519" ) local dropbear_key_types=( "rsa" "ecdsa" "ed25519" )
local dropbear_keyfile_prefix="/etc/dropbear/dropbear_" local dropbear_keyfile_prefix="/etc/dropbear/dropbear_"
local dropbear_keyfile_suffix="_host_key" local dropbear_keyfile_suffix="_host_key"
local openssh_keyfile_prefix="/etc/ssh/ssh_host_" local openssh_keyfile_prefix="/etc/ssh/ssh_host_"
local openssh_keyfile_suffix="_key" local openssh_keyfile_suffix="_key"
# Check we are needed # Check we are needed
if ! sshcs_check_nonempty "${dropbear_authorized_keys}"; then if ! sshcs_check_nonempty "${dropbear_authorized_keys}"; then
echo "There is no root key(s) in ${dropbear_authorized_keys}. Skipping." echo "There is no root key(s) in ${dropbear_authorized_keys}. Skipping."
return 0 return 0
fi fi
if ! sshcs_check_nonempty "${etc_crypttab}"; then if ! sshcs_check_nonempty "${etc_crypttab}"; then
echo "There is no device in ${etc_crypttab}. Skipping." echo "There is no device in ${etc_crypttab}. Skipping."
return 0 return 0
fi fi
umask 0022 umask 0022
sshcs_check_keys sshcs_check_keys
add_checked_modules "/drivers/net/" # Note: parts of this script (modules/binaries/files added) are the same than
# Note: parts of this script (modules/binaries added) are the same than the # other install scripts (/usr/lib/initcpio/install/):
# 'encrypt' install script (/usr/lib/initcpio/install/encrypt) which is the # - 'encryp': nominal support of encrypted volumes at boot time
# nominal one to deal with encrypted volumes at boot time. # - 'net': network tools
add_module dm-crypt
# Note: crypto modules are necessary
if [ -n "${CRYPTO_MODULES}" ]; then
local mod
for mod in ${CRYPTO_MODULES}; do
add_module "${mod}"
done
else
add_all_modules "/crypto/"
fi
# Note: dmsetup is necessary for device mapper features ## Modules
add_binary "cryptsetup" # (from 'encrypt')
add_binary "dmsetup" add_module 'dm-crypt'
add_binary "dropbear" add_module 'dm-integrity'
add_binary "ip" if [[ $CRYPTO_MODULES ]]; then
add_binary "/usr/lib/initcpio/ipconfig" "/sbin/ipconfig" local mod
for mod in $CRYPTO_MODULES; do
# Our hook files add_module "$mod"
[ -e "${sshcs_env}" ] && add_file "${sshcs_env}"
# auth-related files
add_file "/lib/libnss_files.so"
# SSH-related files
add_file "${dropbear_authorized_keys}" "/root/.ssh/authorized_keys"
for keytype in "${dropbear_key_types[@]}"; do
add_file "${dropbear_keyfile_prefix}${keytype}${dropbear_keyfile_suffix}"
done done
else
add_all_modules '/crypto/'
fi
# cryptsetup-related files # (from 'net')
add_file "${etc_crypttab}" add_checked_modules '/drivers/net/'
add_file "/usr/lib/udev/rules.d/10-dm.rules"
add_file "/usr/lib/udev/rules.d/13-dm-disk.rules"
add_file "/usr/lib/udev/rules.d/95-dm-notify.rules"
add_file "/usr/lib/initcpio/udev/11-dm-initramfs.rules" "/usr/lib/udev/rules.d/11-dm-initramfs.rules"
# At least with LUKS v2 volumes, cryptsetup calls pthread_cancel(), which
# dlopen()s libgcc_s.so.1.
# See the nominal 'encrypt' module, and similar/related bug reports (e.g.
# https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=950254).
add_binary "/usr/lib/libgcc_s.so.1"
add_runscript ## Binaries
# (from 'encrypt')
add_binary 'cryptsetup'
# cryptsetup calls pthread_create(), which dlopen()s libgcc_s.so.1
# Note: at least necessary for LUKS v2 volumes.
# Also see similar/related bug reports (e.g. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=950254).
add_binary '/usr/lib/libgcc_s.so.1'
# (from 'net')
add_binary '/usr/lib/initcpio/ipconfig' '/bin/ipconfig'
# (ours)
# Note: dmsetup is necessary for device mapper features
add_binary 'dmsetup'
add_binary 'dropbear'
add_binary 'ip'
add_binary 'ethtool'
## Other files
# (from 'encrypt')
# cryptsetup-related files
map add_udev_rule \
'10-dm.rules' \
'13-dm-disk.rules' \
'95-dm-notify.rules' \
'/usr/lib/initcpio/udev/11-dm-initramfs.rules'
# (ours)
# Our script and options
[ -e "${sshcs_env}" ] && add_file "${sshcs_env}"
# Note: use /usr/local/bin, even though everything actually points to /usr/bin
# in initramfs.
add_file '/usr/lib/initcpio/hooks/ssh-cryptsetup-tools' '/usr/local/bin/ssh-cryptsetup-tools'
# SSH-related files
add_file "${dropbear_authorized_keys}" '/root/.ssh/authorized_keys'
for keytype in "${dropbear_key_types[@]}"; do
add_file "${dropbear_keyfile_prefix}${keytype}${dropbear_keyfile_suffix}"
done
# crypt partitions
add_file "${etc_crypttab}"
add_runscript
} }
help() { help() {
cat <<EOF cat <<EOF
This hook allows for LUKS encrypted devices to be unlocked either locally This hook allows for LUKS encrypted devices to be unlocked either locally
(boot console) or remotely over SSH. (boot console) or remotely over SSH.
@@ -113,13 +132,25 @@ LUKS encrypted devices to unlock are derived from '/etc/crypttab', which must
be present. be present.
Some options can be set in '/etc/initcpio/sshcs_env' (file is sourced in Some options can be set in '/etc/initcpio/sshcs_env' (file is sourced in
initrd shell): initrd shell):
* 'sshcs_opt_timeout_ipconfig': time (s) to configure IP * 'sshcs_opt_debug': whether to be more verbose about ongoing actions
- default: 10 seconds - default: '0'
* 'sshcs_opt_listen': listening port (22 by default) - any non-zero value to enable
* 'sshcs_opt_timeout_poweroff': time (s) to unlock devices before automatic * 'sshcs_opt_net_wol': Wake-on-LAN option to set on network device
powering off - default: 'g' (MagicPacket™)
- default (and minimum value): 2 minutes - usually WOL is disabled once in initramfs shell
- set empty to not change network device WOL setting
* 'sshcs_opt_timeout_ipconfig': time (in seconds) to configure IP
- default: '10'
* 'sshcs_opt_listen': SSH listening port
- default: '22'
* 'sshcs_opt_timeout_poweroff': time (in seconds) to unlock devices before
automatic powering off
- default (and minimum value): '120' (2 minutes)
- negative value to deactivate - negative value to deactivate
* 'sshcs_opt_use_shell': whether to start a full 'ash' shell
- default: '0'
- '1' to enable
- when disabled (the default), a script to unlock devices is executed instead
Each SSH server key ('dropbear_rsa_host_key', 'dropbear_ecdsa_host_key' and Each SSH server key ('dropbear_rsa_host_key', 'dropbear_ecdsa_host_key' and
'dropbear_ed25519_host_key' in '/etc/dropbear' folder) is imported from OpenSSH 'dropbear_ed25519_host_key' in '/etc/dropbear' folder) is imported from OpenSSH