linux_dsm_epyc7002/security
James Bottomley 09a119a2d4 security: keys: trusted: fix TPM2 authorizations
[ Upstream commit de66514d934d70ce73c302ce0644b54970fc7196 ]

In TPM 1.2 an authorization was a 20 byte number.  The spec actually
recommended you to hash variable length passwords and use the sha1
hash as the authorization.  Because the spec doesn't require this
hashing, the current authorization for trusted keys is a 40 digit hex
number.  For TPM 2.0 the spec allows the passing in of variable length
passwords and passphrases directly, so we should allow that in trusted
keys for ease of use.  Update the 'blobauth' parameter to take this
into account, so we can now use plain text passwords for the keys.

so before

keyctl add trusted kmk "new 32 blobauth=f572d396fae9206628714fb2ce00f72e94f2258fkeyhandle=81000001" @u

after we will accept both the old hex sha1 form as well as a new
directly supplied password:

keyctl add trusted kmk "new 32 blobauth=hello keyhandle=81000001" @u

Since a sha1 hex code must be exactly 40 bytes long and a direct
password must be 20 or less, we use the length as the discriminator
for which form is input.

Note this is both and enhancement and a potential bug fix.  The TPM
2.0 spec requires us to strip leading zeros, meaning empyty
authorization is a zero length HMAC whereas we're currently passing in
20 bytes of zeros.  A lot of TPMs simply accept this as OK, but the
Microsoft TPM emulator rejects it with TPM_RC_BAD_AUTH, so this patch
makes the Microsoft TPM emulator work with trusted keys.

Fixes: 0fe5480303 ("keys, trusted: seal/unseal with TPM 2.0 chips")
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Tested-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-05-14 09:50:20 +02:00
..
apparmor
bpf
integrity integrity: double check iint_cache was initialized 2021-03-30 14:31:55 +02:00
keys security: keys: trusted: fix TPM2 authorizations 2021-05-14 09:50:20 +02:00
loadpin
lockdown
safesetid
selinux selinux: add proper NULL termination to the secclass_map permissions 2021-05-14 09:49:59 +02:00
smack smackfs: restrict bytes count in smackfs write functions 2021-03-07 12:34:05 +01:00
tomoyo tomoyo: recognize kernel threads correctly 2021-03-09 11:11:15 +01:00
yama
commoncap.c security: commoncap: fix -Wstringop-overread warning 2021-05-11 14:47:36 +02:00
device_cgroup.c
inode.c
Kconfig
Kconfig.hardening
lsm_audit.c
Makefile
min_addr.c
security.c