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mirror of https://git.code.sf.net/p/linux-ima/ima-evm-utils synced 2025-04-28 06:33:36 +02:00

182 Commits

Author SHA1 Message Date
Petr Vorel
aa636ee486 Add sanity check for file parameter of ima_boot_aggregate
Parameter expects to be a copy of
/sys/kernel/security/tpm0/binary_bios_measurements (i.e. regular file,
not a directory, block or character device, socket, ...)

Fixes: f49e982 ("ima-evm-utils: read the TPM 1.2 binary_bios_measurements")

Signed-off-by: Petr Vorel <pvorel@suse.cz>
[zohar@linux.ibm.com: updated to check stat result]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-19 09:45:55 -04:00
Bruno Meneguele
3e7d575816 ima-evm-utils: fix overflow on printing boot_aggregate
There was no room for placing the '\0' at the end of boot_aggregate value,
thus printf() was reading 1 byte beyond the array limit.

Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 21:49:58 -04:00
Bruno Meneguele
dbbaccc781 ima-evm-utils: fix memory leak in case of error
OpenSSL context should be freed in case of versions >= 1.1 before leaving
the function in case EVP_DigestUpdate() returns any error.

Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 21:49:58 -04:00
Bruno Meneguele
02d976a3df ima-evm-utils: fix empty label at end of function.
Distros running older OpenSSL versions (<= 1.1) fail to build due to the
empty label at the end of calc_bootaggr(). For these, that label is no-op.

Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 21:49:58 -04:00
Mimi Zohar
0911c60fb5 ima-evm-utils: address new compiler complaints
Address the new compiler complaints:
- while reading the template data
- while reading the exported TPM 1.2 PCRs
- while reading the TPM event log

Reported-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 21:49:58 -04:00
Mimi Zohar
4a96edb6e8 ima-evm-utils: verify the template data file signature
The file signature stored in the ima_measurement list is verified based
on the file hash.  Instead of reading the file data to calculate the
file hash, compare with the file hash stored in the template data.  In
both cases, the set of public keys need to be specified.

This patch renames the "--list" option to "verify-sig" option.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 16:25:32 -04:00
Mimi Zohar
1816644727 ima-evm-utils: the IMA measurement list may have too many measurements
Reading the TPM PCRs before walking the measurement list guarantees
the measurement list contains all the records, possibly too many records.
Compare the re-calculated hash after each extend with both the per bank
TPM PCR digests and the SHA1 paddeded TPM PCR digests.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 16:25:32 -04:00
Mimi Zohar
6baaf7f876 ima-evm-utils: guarantee the measurement list contains all the records
Reading the TPM PCRs before walking the measurement list guarantees
the measurement list contains all the records.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 16:25:32 -04:00
Mimi Zohar
36aa7be850 ima-evm-utils: emit "ima_measurement" messages based on log level
"ima_measurement" emits quite a few messages.  Only a few messages
belong at the default log level.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 16:25:32 -04:00
Mimi Zohar
354510fa50 ima-evm-utils: support providing the TPM 1.2 PCRs as a file
"evmctl ima_measurement" walks the IMA measurement list calculating the
PCRs and verifies the calculated values against the system's PCRs.
Instead of reading the system's PCRs, provide the PCRs as a file.  For
TPM 1.2 the PCRs are exported via a securityfs file.

Verifying the IMA measurement list against the exported TPM 1.2 PCRs
file may be used remotely for regression testing.  If used in a
production environment, the provided TPM PCRs must be compared with
those included in the TPM 1.2 quote as well.

This patch defines an evmctl ima_measurement "--pcrs <filename>" option.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 16:25:31 -04:00
Mimi Zohar
d5b24fa18e ima_evm_utils: support extending TPM 2.0 banks w/original SHA1 padded digest
Initially the sha1 digest, including violations, was padded with zeroes
before being extended into the other TPM banks.  Support walking the
IMA measurement list, calculating the per TPM bank SHA1 padded
digest(s).

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 16:25:31 -04:00
Mimi Zohar
b102db4180 ima-evm-utils: improve reading TPM 1.2 PCRs
Instead of reading the TPM 1.2 PCRs one at a time, opening and closing
the securityfs file each time, read all of PCRs at once.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-15 16:25:24 -04:00
Mimi Zohar
663dfd5efb ima-evm-utils: mixed "ima" and other template formats not supported
An IMA measurement list may not contain "ima" and other template
formats.  Fail verifying the ima_measurement test.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:44 -04:00
Mimi Zohar
f49e982627 ima-evm-utils: read the TPM 1.2 binary_bios_measurements
Instead of just calculating the "boot_aggregate" based on the current
TPM PCRs, the original LTP and standalone ima_boot_aggregate test walked
the TPM 1.2 event log, calculating the PCRs.

If the TPM 1.2 event log is provided as an option on the "evmctl
ima_boot_aggregate" command, read the event log, calculate the sha1
PCRs, and calculate the "boot_aggregate" based on these PCRs.

The code for walking the IMA measurement list is based on the LTP and
standalone ima_boot_aggregate tests.  Similar support for reading the
TPM 2.0 event log to calculate the PCRs requires the TPM 2.0 event log
to be exported or a TSS to read the event log.  Parsing the TPM 2.0
event log is not supported here.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:44 -04:00
Mimi Zohar
81aa698c70 ima-evm-utils: support the original "ima" template
The original "ima" template digest included just a SHA1 file data hash
and a fixed 255 character pathname in the hash calculation.  Two main
differences exist between the "ima" template and other template formats.
The other template data formats are prefixed with the template data
length and each field is prefixed with the field length,

These differences simplify verifying the other template formats against
the TPM PCRs without necessarily understanding each and every template
field.

Support for the original "ima" templat formate is based on the original
LTP and IMA standalone versions.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:44 -04:00
Mimi Zohar
d9f015035a ima-evm-utils: use uint32_t for template length
The template length should never be less than zero.  Replace "int" with
"uint32_t".

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:21 -04:00
Mimi Zohar
ff26f9704e ima-evm-utils: calculate and verify the template data digest
Validating a TPM quote of PCR-10, the default IMA PCR, requires not only
sending the quote to the verifier, but the IMA measurement list as well.
The attestation server can verify the IMA measurement list simply by
walking the measurement list and re-calculating the PCRs based on the
template data digest.  In addition, the attestation server could verify
the template data digest based on the template data.

The LTP and standalone "ima_measure" test optionally verify the template
data digest.  Similarly add "--verify" support to conditionally verify
the template data digest against the template data.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:21 -04:00
Mimi Zohar
bb62a7115e ima-evm-utils: don't hardcode validating the IMA measurement list
File time of measure, time of use (ToMToU) violations are annotated in
the measurement list by including a template data digest of zeroes, but
extending the TPM with 0xFF's.  This causes validating the measurement
against the TPM PCRs to fail.  To validate the measurement list against
the PCRs requires replacing the zero template data digest with OxFF's.

The default behavior, unless specifically requested, should be to fail
the measurement list verification.  Support validating the measurement
list based on a "--validate" option.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:21 -04:00
Mimi Zohar
747bf9e890 ima-evm-utils: fix measurement violation checking
The template data digest for file measurement time of measure, time of
use (ToMToU) violations is zero.  Don't calculate the template data
digest for the different banks.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:21 -04:00
Mimi Zohar
8b49f0c01c ima-evm-utils: fix PCRAggr error message
Display the correct TPM PCR value.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-07-09 11:00:21 -04:00
Maurizio
319fb19caa ima_evm_utils: extended calc_bootaggr to PCRs 8 - 9
cal_bootaggr() should include PCRs 8-9 in non-SHA1 digests.

Signed-off-by: Maurizio Drocco <maurizio.drocco@ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-06-24 20:36:05 -04:00
Mimi Zohar
917317a8ea ima_evm_utils: emit the per TPM PCR bank "boot_aggregate" values
Instead of emitting the per TPM PCR bank "boot_aggregate" values one
at a time, store them in a buffer and emit them all at once.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-06-11 17:14:57 -04:00
Mimi Zohar
dc00c92adf ima-evm-utils: calculate the per TPM bank boot_aggregate
The IMA measurement list boot_aggregate is the link between the preboot
event log and the IMA measurement list.  Read and calculate all the
possible per TPM bank boot_aggregate digests based on PCRs 0 - 7.

Reading the TPM PCRs requires root permission, unless access to the
device (/dev/tpm0 or /dev/tpmrm0) has been granted.

Prior to calculating the boot_aggregate, the TPM PCRs themselves should
be validated by walking the TPM event log and re-calculating the PCRs.
(Such a test should be included as part of the TSS regression testsuites.)

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:29:59 -04:00
Patrick Uiterwijk
03f99ea6d0 ima-evm-utils: Add support for Intel TSS2 for PCR reading
This patch makes it possible to use the Intel TSS2 for getting
PCR values from the SHA1/SHA256 banks on a TPM2.
It is somewhat naive as it doesn't use the multi-PCR selection
that TSS2 is capable of, that is for a future patch.

Signed-off-by: Patrick Uiterwijk <patrick@puiterwijk.org>
[zohar@linux.ibm.com: added missing "stdint.h" in pcr_tsspcrread.c]
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:28:00 -04:00
Mimi Zohar
e532fb65fd ima-evm-utils: remove TPM 1.2 specific code
Now that read_tpm_banks() reads the TPM 1.2 PCRs, remove the TPM 1.2
specific code for reading and verifying the SHA1 PCRs.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:25:13 -04:00
Mimi Zohar
040c693b8b ima-evm-utils: use a common bank variable for TPM 1.2 and TPM 2.0
Extend read_tpm_banks() to support TPM 1.2, by reading TPM 1.2 SHA1 PCRs
into the first bank and mark the other banks as disabled.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:25:11 -04:00
Mimi Zohar
acf2ac7559 ima-evm-utils: compare re-calculated PCRs with the TPM values
After walking the measurement list, re-calculating and extending the TPM
PCRs with the appropriate template digest for each bank, compare the
re-calculated PCR values for each TPM bank with the actual TPM values.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:25:09 -04:00
Mimi Zohar
3472f9ba9c ima-evm-utils: read the PCRs for the requested TPM banks
Read and store the PCRs for the requested banks to compare with the
re-calculated PCR values.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:25:01 -04:00
Mimi Zohar
2f482a6989 ima-evm-utils: add support in tpm2_read_pcrs to read different TPM banks
tpm2_read_pcrs() reads the sha1 PCRs in order to verify the measurmeent
list.  This patch adds support for reading other TPM banks.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:24:59 -04:00
Mimi Zohar
696bf0b108 ima-evm-utils: calculate the digests for multiple TPM banks
IMA currently extends the different TPM banks by padding/truncating the
SHA1 template digest.  Although the IMA measurement list only includes
the SHA1 template digest, the template digest could be re-calculated
properly for each bank.

This patch adds support for properly calculating the template hash for
multiple TPM banks - "sha1" and "sha256".

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:24:55 -04:00
Mimi Zohar
bdc94c9b49 ima-evm-utils: increase the size of "zero" and "fox" variables
Opening a file for write when it is already opened for read, results in
a time of measure, time of use (ToMToU) error.  Similarly, when opening
a file for read, when it is already opened for write, results in a file
measurement error.  These violations are flagged by including 0x00's as
the template digest in the measurement list, but extending the TPM with
0xFF's.

In preparation of extending the TPM banks with bank specific digest
values, increase the "zero" and "fox" variable sizes.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:24:48 -04:00
Mimi Zohar
dc3897f011 ima-evm-utils: treat unallocated banks as an error
The TPM spec differentiates between an unknown bank and an unallocated
bank.  In terms of re-calculating the PCR, treat them as equivalent.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:24:44 -04:00
Vitaly Chikunov
9c2298c367 ima-evm-utils: Never exit with -1 code
Change main() return code from -1 to 125 as -1 is not really valid exit
code. 125 is choosen because exit codes for signals start from 126.

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2020-05-19 17:24:37 -04:00
Vitaly Chikunov
cf1b8fda8d ima-evm-utils: Allow EVM verify to determine hash algo
Previously for EVM verify you should specify `--hashalgo' option while
for IMA ima_verify you didn't.

Allow EVM verify to determine hash algo from signature.

Also, this makes two previously static functions to become exportable
and renamed:

  get_hash_algo_from_sig -> imaevm_hash_algo_from_sig
  get_hash_algo_by_id    -> imaevm_hash_algo_by_id

This is needed because EVM hash is calculated (in calc_evm_hash) outside
of library.

imaevm_hash_algo_by_id() will now return NULL if algo is not found.

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-30 13:32:28 -04:00
Vitaly Chikunov
90176e835a ima-evm-utils: Do not load keys from x509 certs if user pass --rsa
If user wants to verify v1 signature and specify RSA public key in `-k'
option, this key will be attempted to be loaded as x509 certificate and
this process will output errors.

Do not load a key as a x509 cert if user pass `--rsa'.

This is not perfect solution. As now it's possible to specify `-k' and
`--rsa' and v2 signatures will not verify, because of no keys.

This improvement is not added into ima_measurement().

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-30 13:32:28 -04:00
Vitaly Chikunov
2b491be5e2 ima-evm-utils: Fix ima_verify return value on multiple files
If any tested file results in failure produce failure exit code.
Previously exit code affected only by the last file tested.

Fixes: "Allow multiple files in ima_verify"
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-30 07:33:56 -04:00
Mimi Zohar
bd8b503206 ima-evm-utils: limit OPENSSL_init_crypto calls
OPENSSL_init_crypto() was introduced in version 1.1.  When using an
older version of openssl, don't call OPENSSL_init_crypto.  Partially
revert commit 782224f33cd7 ("ima-evm-utils: Rework openssl init").

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-30 07:15:18 -04:00
Vitaly Chikunov
c317d4618f ima-evm-utils: Namespace some too generic object names
Prefix `dump', `do_dump', and `params' with `imaevm_' to avoid colliding
with other global symbols.
Also, rename `libevm_' to `libimaevm_`, only used with `params'.
Additionally, rename `dump' into `hexdump'.
Finally, rename `get_hash_algo' to `imaevm_get_hash_algo' as suggested by
Mimi Zohar.

Lines that became too long are split, indent corrected. No code changes.

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Reviewed-by: Bruno E. O. Meneguele <bmeneg@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-25 12:14:21 -04:00
Vitaly Chikunov
a1b149bda4 ima-evm-utils: Show used hash algo in verbose mode
This could be useful for users.

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-25 12:14:10 -04:00
Vitaly Chikunov
25fce6e76a ima-evm-utils: Do not allow fallback and unknown hash algos
Falling back and permissiveness could have security implications.

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-25 12:14:01 -04:00
Mimi Zohar
31ceff7eb6 ima-evm-utils: use tsspcrread to read the TPM 2.0 PCRs
The kernel does not expose the crypto agile TPM 2.0 PCR banks to
userspace like it exposes PCRs for TPM 1.2.  As a result, a userspace
application is required to read PCRs.

This patch adds tsspcrread support for reading the TPM 2.0 PCRs.
tsspcrread is one application included in the ibmtss package.

Sample error messages:
Failed to read PCRs: (tsspcrread failed: No such file or directory)
Failed to read PCRs: (TSS_Dev_Open: Error opening /dev/tpmrm0)

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Bruno E. O. Meneguele <bmeneg@redhat.com>
2019-07-24 06:09:17 -04:00
Mimi Zohar
388f807a0f ima_evm_utils: erroneous "verification failed: 0 (invalid padding)" message
When public keys are specified on the boot command line (--key "<public
key file>,[<public key file>,...]"), the appropriate public key is used
to verify EVM or file signatures.  If no keys are specified, the default
x509_evm.der or pubkey_evm.pem file is used to verify the DIGSIG_VERSION_2
or DIGSIG_VERSION_1 signatures respectively, without first checking the
keyids.  Instead of emitting a "verification failed: 0 (invalid
padding)" message, an "unknown keyid" message would be clearer.

To address this problem, when no public keys are specified, this patch
loads the x509_evm.der default public key onto the "public_keys" list,
while the pubkey_evm.pem continues to be passed to verify_hash_v1()

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-18 21:07:48 -04:00
Vitaly Chikunov
08a51e7460 ima-evm-utils: Fix file2bin stat and fopen relations
Check stat(2) return value, use fstat(2) to avoid race between
stat() and fopen(), remove now unused get_filesize().

Fixes: CID 229889.
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-16 14:14:03 -04:00
Vitaly Chikunov
9d52489bd3 ima-evm-utils: Fix memory leak in get_password
Free allocated password buffer when returning NULL.

Fixes: CID 229894 (partially).
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-16 14:13:50 -04:00
Vitaly Chikunov
4b7a74cc41 ima-evm-utils: Fix possible xattr_value overflows in calc_evm_hash
`selinux_str',`caps_str', and `ima_str' are passed from the command line
but copied into the fixed-size buffer.

Yes, length of `selinux_str' is calculated differently than of `caps_str'.

Fixes: CID 229895.
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-16 14:13:39 -04:00
Vitaly Chikunov
d47951c6e1 ima-evm-utils: Fix null dereference from file2bin to memcpy
file2bin() may return NULL, which is set to tmp, which is passed to
memcpy. Add explicit check for it.

Fixes: CID 229904.
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-16 14:12:47 -04:00
Mimi Zohar
164c51ff2b ima-evm-utils: support template "buf" field
Other than the "boot-aggregate" measurement entry in the IMA
measuremeent list, all other measurements are of file data.  Kernel
support was recently added to support measuring the kexec boot command
line buffer, which is stored in a new template field named 'buf'.

This patch adds support for a new template named "ima-buf", defined as
"d-ng|n-ng|buf".

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-08 10:00:13 -04:00
Mimi Zohar
4ec7c1d028 ima-evm-utils: limit "remain unprocessed data" messages
New, unknown template formats containing unknown fields are not
processed, resulting in "remain unprocessed data" messages.  Processing
these unknown fields is unnecessary for walking the measurement list to
re-calculate the PCRs.

The "remain unproccessed data" may also be emitted for malformed, known
template records.

This patch limits the number of messages emitted to once per template
format and includes the template name in the message.

Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-08 10:00:13 -04:00
Vitaly Chikunov
ae57a3e1e4 ima-evm-utils: Allow multiple files in ima_verify
This allows testing multiple verify in a row, similar to ima_measurement.

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-08 10:00:13 -04:00
Vitaly Chikunov
556f2fc66d ima-evm-utils: Preload public keys for ima_verify
This allows testing verify_hash_v2() with multiple public keys.

Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
2019-07-08 10:00:13 -04:00