cryptsetup2 2.6.1 is a new release that supports reencryption of Q4.2 release LUKS2 volumes created at installation.
This is a critical feature for the Qubes OS 4.2 release for added data at rest protection
Cryptsetup 2.6.x internal changes:
- Argon2 used externally and internally: requires a lot of RAM and CPU to derivate passphrase to key validated in key slots.
- This is used to rate limit efficiently bruteforcing of LUKS key slots, requiring each offline brute force attempt to consume ~15-30 seconds per attempt
- OF course, strong passphrases are still recommended, but bruteforcing LUKSv2 containers with Argon2 would require immense time, ram and CPU even to bruteforce low entropy passphrase/PINs.
- passphrase change doesn't permit LUKS key slot specification anymore: key slot rotates (new one consusumed per op: then old one wiped internally. EG: LUKS key slot 1 created, then 0 deleted)
- reencryption doesn't permit old call arguments. No more direct-io; inadmissively slow through AIO (async) calls, need workarounds for good enough perfs (arguments + newer kernel with cloudfare fixes in tree)
cryptsetup 2.6.1 requires:
- lvm2 2.03.23, which is also included in this PR.
- requires libaio, which is also included in this PR (could be hacked out but deep dependency at first sight: left in)
- requires util-linux 2.39
- patches for reproducible builds are included for above 3 packages.
luks-functions was updated to support the new cryptsetup2 version calls/changes
- reencryption happen in direct-io, offline mode and without locking, requiring linux 5.10.9+ to bypass linux queues
- from tests, this is best for performance and reliability in single-user mode
- LUKS container ops now validate Disk Recovery Key (DRK) passphrase prior and DRK key slot prior of going forward if needed, failing early.
- Heads don't expect DRK to be in static key slot anymore, and finds the DRK key slot dynamically.
- If reencrytipn/passphrase change: make sure all LUKS containers on same block device can be unlocked with same DRK
- Reencryption: requires to know which key slot to reencrypt.
- Find LUKS key slot that unlocks with DRK passphrase unlock prior of reencrypt call
- Passphrase change: no slot can be passed, but key slot of DRK rotates.
kexec-seal-key
- TPM LUKS Disk Unlock Key key slots have changed to be set in max slots per LUKS version (LUKSv1:7 /LUKSv2: 31)
- If key slot != default LUKS version's keyslot outside of DRK key slot: prompt the user before wiping that key slot, otherwise wipe automatically
- This takes for granted that the DRK key slot alone is needed on the system and Heads controls the LUKS key slots.
- If user has something else going on, ie: Using USB Security dongle + TPM DUK, then the user will need to say no when wiping keys.
- It was suggested to leave LUKS key slots outside of DRK alone, but then: what to do when all key slots would be used?
- Alternative implementation could be to only prompt users to wipe keyslots other then DRK when key slots are all used (LUKSv1: 0-7, LUKSv2: 0-31)
- But then cleanup would need to happen prior of operations (LUKS passphrase change, TPM DUK setup) and could be problematic.
- LUKS containers now checked to be same LUKS version prior of permitting to set TPM DUK and will refuse to go forward of different versions.
TODO:
- async (AIO) calls are not used. direct-io is used instead. libaio could be hacked out
- this could be subject to future work
Notes:
- time to deprecated legacy boards the do not enough space for the new space requirements
- x230-legacy, x230-legacy-flash, x230-hotp-legacy
- t430-legacy, t430-legacy-flash, t430-hotp-legacy already deprecated
Unrelated:
- typos fixes found along the way
Signed-off-by: Thierry Laurion <insurgo@riseup.net>
TODO:
- $(pcrs) call sometimes fail in DEBUG call, outputting too many chars to be inserted in kmesg. Call removed here since redundant (PCR6 already extended with LUKS header)
- Notes added for TPM2 simplification over TPM1 in code as TODO
Signed-off-by: Thierry Laurion <insurgo@riseup.net>
Exception: scripts sourcing/calls within etc/ash_functions continues to use old TRACE functions until we switch to bash completely getting rid of ash.
This would mean getting rid of legacy boards (flash + legacy boards which do not have enough space for bash in flash boards) once and for all.
Signed-off-by: Thierry Laurion <insurgo@riseup.net>
When playing with long fbwhiptail/whiptail messages, this commit played around the long string using fold.
'''
echo -e "This will replace the encrypted container content and its LUKS Disk Recovery Key.\n\nThe passphrase associated with this key will be asked from the user under the following conditions:\n 1-Every boot if no Disk Unlock Key was added to the TPM\n 2-If the TPM fails (hardware failure)\n 3-If the firmware has been tampered with/modified by the user\n\nThis process requires you to type the current LUKS Disk Recovery Key passphrase and will delete the LUKS TPM Disk Unlock Key slot, if set up, by setting a default boot LUKS key slot (1) if present.\n\nAt the next prompt, you may be asked to select which file corresponds to the LUKS device container.\n\nHit Enter to continue." | fold -w 70 -s
'''
Which gave the exact output of what will be inside of the fbwhiptail prompt, fixed to 70 chars width:
'''
This will replace the encrypted container content and its LUKS Disk
Recovery Key.
The passphrase associated with this key will be asked from the user
under the following conditions:
1-Every boot if no Disk Unlock Key was added to the TPM
2-If the TPM fails (hardware failure)
3-If the firmware has been tampered with/modified by the user
This process requires you to type the current LUKS Disk Recovery Key
passphrase and will delete the LUKS TPM Disk Unlock Key slot, if set
up, by setting a default boot LUKS key slot (1) if present.
At the next prompt, you may be asked to select which file corresponds
to the LUKS device container.
Hit Enter to continue.
'''
Therefore, for long prompts in the future, one can just deal with "\n 1-" alignments to be respected in prompts and have fold deal with cutting the length of strings properly.
Signed-off-by: Thierry Laurion <insurgo@riseup.net>
Changes:
- As per master: when TOTP cannot unseal TOTP, user is prompted to either reset or regenerate TOTP
- Now, when either is done and a previous TPM Disk Unlock Key was setuped, the user is guided into:
- Regenerating checksums and signing them
- Regenerating TPM disk Unlock Key and resealing TPM disk Unlock Key with passphrase into TPM
- LUKS header being modified, user is asked to resign kexec.sig one last time prior of being able to default boot
- When no previous Disk Unlock Key was setuped, the user is guided into:
- The above, plus
- Detection of LUKS containers,suggesting only relevant partitions
- Addition of TRACE and DEBUG statements to troubleshoot actual vs expected behavior while coding
- Were missing under TPM Disk Unlock Key setup codepaths
- Fixes for #645 : We now check if only one slots exists and we do not use it if its slot1.
- Also shows in DEBUG traces now
Unrelated staged changes
- ash_functions: warn and die now contains proper spacing and eye attaction
- all warn and die calls modified if containing warnings and too much punctuation
- unify usage of term TPM Disk Unlock Key and Disk Recovery Key
Basic mode allows (but does not require) setting a default boot option.
Don't seal disk unlock keys in Basic mode.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Remove brand name from this configuration variable. For backward
compatibility, update config.user in init if the branded variable is
present.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
PureBoot Basic mode provides the full Linux userspace in firmware from
Heads without requiring verified boot or a Librem Key. Basic and
verified boot can be switched freely without changing firmware, such as
if a Librem Key is lost.
PureBoot Basic can apply firmware updates from a USB flash drive, and
having a complete Linux userspace enables more sophisticated recovery
options.
Basic mode boots to the first boot option by default, setting a default
is not required. This can be configured in the config GUI.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
- /tmp/initrd_extract was attempted to be deleted while under that directory when no crypptab found.
- changing of directory to / is non-conditional prior of deletion: move to cleaning step
- Clarity on message displayed to user when a generic crypttab will be generated in case of no OS override
gui-init: do not consume two unseal attempt to unseal both totp and hotp + cosmetic changes (slow down TPM DA lockout)
kexec-seal-key: Add DEBUG statement for PCR precalc
seal-totp: add DEBUG statements regarding skipping of PCR5 and PCR6 involvement into TOTP/HOTP sealing ops
seal-hotpkey: Add DEBUG statements related to reuse of TOTP sealed secret
tpmr: add DO_WITH_DEBUG calls to output pcrread and extend calls
tpmr: typo correction stating TRACE calls for tpm2 where it was for tpm1
tpmr: add DO_WITH_DEBUG calls for calcfuturepcr
functions: Cosmetic fix on pause_recovery asking user to press Enter to go to recovery shell on host console when board defines CONFIG_BOOT_RECOVERY_SERIAL
Not so related but part of output review and corrections:
kexec-insert-key: cosmetic changes prepending "+++" to disk related changes
kexec-save-default: cosmetic changes prepending "+++" to disk related changes
config/coreboot-qemu-tpm*.config: add ccache support for faster coreboot rebuild times
Most logic throughout Heads doesn't need to know TPM1 versus TPM2 (and
shouldn't, the differences should be localized). Some checks were
incorrect and are fixed by this change. Most checks are now unchanged
relative to master.
There are not that many places outside of tpmr that need to
differentiate TPM1 and TPM2. Some of those are duplicate code that
should be consolidated (seal-hotpkey, unseal-totp, unseal-hotp), and
some more are probably good candidates for abstracting in tpmr so the
business logic doesn't have to know TPM1 vs. TPM2.
Previously, CONFIG_TPM could be variously 'y', 'n', or empty. Now it
is always 'y' or 'n', and 'y' means "any TPM". Board configs are
unchanged, setting CONFIG_TPM2_TOOLS=y implies CONFIG_TPM=y so this
doesn't have to be duplicated and can't be mistakenly mismatched.
There were a few checks for CONFIG_TPM = n that only coincidentally
worked for TPM2 because CONFIG_TPM was empty (not 'n'). This test is
now OK, but the checks were also cleaned up to '!= "y"' for robustness.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Resetting the TPM creates a new primary object, and there is no reason
for kexec-save-default to sign an old hash. Always update the hash
instead of creating it only if it doesn't exist.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
-coreboot support of TPM v2.0 (shared config for TPM2 support across all 4 previous variations)
-swtpm set to be launched under TPM v2.0 mode under board config
-Documentation file under each board.md softlinks to qemu-coreboot-fbwhiptail-tpm1.md (which has been generalized)
This is skeleton for TPM v2 integration under Heads
-------------
WiP
TODO:
- libcurl cannot be built as a tpm2-tools dependency as of now not sure why. curl currently needs to be added in board config to be built
- Note: tpm-reset (master and here) needs some review, no handle of no tpm use case. Caller is responsible to not call it otherwise does nothing
- init tries to bind fd and fails currently
- Note: Check if whiptail is different of fbwhiptail in clearing screen. As of now every clear seems to be removed, still whiptail clears previous console output
- When no OS' /boot can be mounted, do not try to TPM reset (will fail)
- seal-hotpkey is not working properly
- setting disk unlock key asks for TPM ownership passphrase (sealing in NV requires ownership, but text is misleading user as if reowning TPM)
- We should cache input, feed tpm behind the scene and wipe passphrase and state clearly that this is TPM disk unlock kye passphrase.
- primary key from TPM2 is invalid most of the time from kexec-select-boot and verifying global hashes but is setuped correctly at disk unlock key setup
- would be nice to take advantage of bash function tracing to understand where we are for debugging purposes, code takes ash in consideration only
- tpmr says it implements nv calls but actually doesn't. Removing those falsely wrapped functions would help.
- Implementing them would be better
- REVIEW TODOS IN CODE
- READD CIRCLECI CONFIG
Current state:
- TPM unseal works without disk unlock key and generates TOTP properly (was missing die condition at unseal to not produce always good TOTP even if invalid)
- TPM disk encryption key fails. Hypothesis is that sealing with USB drivers loaded and measures in inconsistent with sealed with/without.
- TPM disk unsealing happens without USB modules being loaded in non-HOTP setup. This fails.
- Current tests are with fbwhiptail (no clear called so having traces on command line of what happens)
- Testing with HOTP implementation for sealing/unsealing since that forces USB module loads on each boot to remove this from failing possibilities
- Add TRACE function tracing output under etc/functions, depending on CONFIG_ENABLE_FUNCTION_TRACING_OUTPUT enabled in board configs
- Replace current DEBUG to TRACE calls in code, reserving DEBUG calls for more verbose debugging later on (output of variables etc)
- add 'export CONFIG_ENABLE_FUNCTION_TRACING_OUTPUT=y' in qemu-coreboot(fb)whiptail-tpm1(-hotp) boards to see it in action
- kexec-save-default extracts initrd crypttab files and creates /boot/kexec_initrd_crypttab_overrides.txt entries pointing to /secret.key
- kexec-insert-key applies /boot/kexec_initrd_crypttab_overrides.txt to replace initrd's crypttabs files pointing to inserted /secret.key through cpio
- Both scripts inform the user of applied magic on screen
Update_checksum was already changing files in /boot, befor checking for
gpg card. If no card is present, the user will end up in the recovery
next time instead of getting the same dialog again. Therefore, the
confirm_gpg_card should be checked before altering files.
The dead -u flag/$update_counter is used to mark the necessisty to
update the hash files now.
Changing the default boot was failing because remove the old entries did
not work as `rm "/some/path/*.txt"` does not work as intended, e.g. the
asterisk is no catch-all.
Add CONFIG_TPM_NO_LUKS_DISK_UNLOCK to allow Librem boards to opt
out of using TPM to store LUKS key, and use it to guard the user
option to add the disk encryption key to the TPM.
Select this option for all Librem boards; all other boards which
select CONFIG_TPM=y will have no change in functionality.
Signed-off-by: Matt DeVillier <matt.devillier@puri.sm>
As part of the config gui we want to be able to have the system define
new config options without them being lost if the user makes their own
changes in CBFS. To allow that this change creates a function initiated
in init that combines all /etc/config* files into /tmp/config. All
existing scripts have been changed to source /tmp/config instead of
/etc/config. The config-gui.sh script now uses /etc/config.user to hold
user configuration options but the combine_configs function will allow
that to expand as others want to split configuration out further.
As it stands here are the current config files:
/etc/config -- Compiled-in configuration options
/etc/config.user -- User preferences that override /etc/config
/tmp/config -- Running config referenced by the BIOS, combination
of existing configs
if "CONFIG_TPM=y" is not present in the config file, functionalities
needing TPM could be disabled, while leaving other functionalities intact.
This will make Heads a more general-usage bootloader payload atop coreboot.
Closes issue #226
Also changed to procedure to show LVM volume groups and block
device ids to aid in choosing the right combination during the
TPM LUKS key sealing process.
Changed the checking of required hashes or required rollback state
to be right before boot, allowing the user to sign/set defaults
in interactive mode.
Also cleaned up usages of recovery and fixed iso parameter
regression.
Similar to qubes-update, it will save then verify the hashes of
the kexec files. Once TOTP is verified, a normal boot will verify
that the file hashes and all the kexec params match and if
successful, boot directly to OS.
Also added a config option to require hash verification for
non-recovery boots, failing to recovery not met.
