Problem
When using a custom password for TPM, the OEM re-ownership process is broken
Impact
The OEM re-ownership process breaks for any user setting a custom password and not just using 12345678
First appeared
6923fb5e20
Detail
on line 498, if blank, the TPM custom password is overwritten with TPM_PASS_DEF (eg, when no custom password is set by the user installing)
```
if [ "$TPM_PASS" == "" ]; then TPM_PASS=$TPM_PASS_DEF; fi
```
so far so good. $TPM_PASS should be used for all TPM interaction from this point. $TMP_PASS_DEF is now a disposed of variable.
we see that happens when resetting the TPM on line 712 (generate_checksums) is that $TPM_PASS is used (correctly)
```## reset TPM and set password
if [ "$CONFIG_TPM" = "y" ]; then
echo -e "\nResetting TPM...\n"
tpmr reset "$TPM_PASS" >/dev/null 2>/tmp/error
---SNIP
```
The TPM now has either the custom password of the user, or the default of 12345678 depending on user selection.
On line 712, we duck into the generate_checksums sub, which for some reason reverts to TPM_PASS_DEF
```
# create Heads TPM counter
if [ "$CONFIG_TPM" = "y" ];then
if [ "$CONFIG_IGNORE_ROLLBACK" != "y" ]; then
tpmr counter_create \
-pwdo "$TPM_PASS_DEF" \
--SNIP
```
This then, rightly, fails due to
```
Authentication failed (Incorrect Password) (ox1) from TPM_CreateCounter
```
This patch adds ARCH="$(LINUX_ARCH)" to Linux targets working on config
files. Without it, the architecture defaults to that of host, which for
cross-compilation isn't right.
Signed-off-by: Krystian Hebel <krystian.hebel@3mdeb.com>
- /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
- Based on initial server board
- Uses whiptail as opposed to fbwhiptail (was slow and output fuzzy)
- Simple fix to have dual KVM(BMC) and vga output for consoles
Reasoning for dropping fbwhiptail support is that:
- it is impossible to output framebuffer content through remote BMC console.
- A workstation board config could output to fbwhiptail for VGA and give remote recovery shell access through BMC
- If someone shows interest for that, qemu-coreboot-tpm boards can be used as reference.
- slowness/fuzzyness of fbwhiptail output through AST would still need to be fixed in kernel drivers. Not a priority here.
Limitation:
- Since whiptail is sent to both consoles:
- If one console goes to recovery shell, recovery shell access invalidate TPM PCR4 measurements.
- The other console won't be aware that TPM measurements were invalidated, and will consequently:
- not be able to unseal TOTP if refreshed
- not be able to unseal TPM disk unlock key on default boot
- A reboot will fix this.
TPM password must be 1-32 characters. Loop if the password is not
valid or the repeated password doesn't match, so the user can try
again.
Move prompt_new_owner_password to functions and use in both gui-init
and tpm-reset.
Fixes#1336
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
They're the same other than a TRACE, combine them. Use busybox
insmod since the insmod script uses bash, we don't need the TPM PCRs on
legacy-flash-boards.
Remove PCR4 extend, these boards lack TPM configuration. Update ROM
example name.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
init must use busybox ash because it is used on legacy-flash boards.
Change shebang, move needed functions to ash_functions.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Multiple traps overwrite each other. While no tpmr functions have more
than one trap right now, it is fragile, and the quoting is complex due
to double expansion. Use at_exit to add exit handlers that accumulate
and do not require special quoting.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Disable all optional algorithms except SM3. (SHA and AES are not
optional.) tpm2-tss uses SHA, AES, and SM3. Reduces size of libcrypto
by almost 1 MB, saves about 140 KB in ROM.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
tpm-reset is just a prompt for the password followed by tpmr reset.
oem-factory-reset already bypasses the prompt, just call tpmr reset
directly.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
These were still writing some debugging output containing flags and
PCRs even when debug was not enabled. Use DEBUG.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
We just set the TPM owner password, so there's no need to make the user
enter it again. Eliminates some failure modes if the user mistypes it
or enters the wrong password.
Allow optionally passing in the TPM owner password in tpmr seal,
check_tpm_counter(), seal-totp, and generate_totp_htop(). The user is
still prompted if the password is needed but was not provided, so
existing uses in other contexts continue to work unchanged.
Prompt for the password in reset_tpm() and pass it down to each of the
above.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Heads doesn't use the endorsement hierarchy, but we shouldn't leave it
with an empty password following a tpm2 clear.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Don't hash password used to seal an object. This limits the password
to 32-characters but avoids obfuscating the usage of the password. The
32-character limit is considered acceptable because password limits are
lower already (GPG token limits to 25 chars). We may allow >32 char
passwords in the future by hashing only if the password is >32 chars.
Always pass passwords as hex to tpm2-tools to avoid possible ambiguity
if the password begins with a control prefix like 'hex:' or 'file:'.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Set consistent dictionary lockout parameters suited to Heads. Disable
lockout reset by setting a random password.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
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
We already have HMAC sessions for encryption and decryption, there's no
need to create an ad-hoc session in tpm2_unseal.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
tpm2-tools is able to log pcap files of TPM2 commands, which can be
inspected with wireshark. Add CONFIG_TPM2_CAPTURE_PCAP to capture
these from the tpmr wrapper, and enable for qemu TPM2 boards.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
TPM2 must be prepared for shutdown, or it may track an auth failure for
dictionary attack prevention (per the spec, to prevent an attack by
attempting to authenticate and then powering off the TPM before it can
update the nonvolatile counter).
Add tpmr shutdown to prepare for shutdown (no-op on TPM1). Invoke it
from poweroff and reboot.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Provide tpmr commands pcrread, pcrsize, calcfuturepcr, and seal for
both TPM1 and TPM2.
Combine seal logic for TPM1/TPM2 in seal-totp, kexec-seal-key. This is
essentially the TPM2 logic now that tpmr provides the same wrapped
commands for both TPM1 and TPM2.
Remove algorithm prefix from PCR list in tpmr unseal for consistency
with tpmr seal.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Update to branch including tpm pcrread until it is merged upstream. tpm
pcrread allows us to use the same logical flow for TPM1 and TPM2 in
seal operations.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
tpmr extend with -ic (extend with literal data) was adding a newline,
use echo -n so it only includes the data given in the hash.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
Clean up TODO comments.
Clean up redirections for tpm2 pcrread, use bash redirect to command.
Use DO_WITH_DEBUG --mask-position to trace tpmr seal for TPM2 and hide
the password.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
No need to test whether bash is a symlink, bash ships on all boards
using the normal init script now.
Signed-off-by: Jonathon Hall <jonathon.hall@puri.sm>
